US2579304A - Self-adjusting recirculating overflow - Google Patents

Description

Dec. 18, 1951 .1. a. CRAWFORD SELF-ADJUSTING RECIRCULATING OVERF'LOW Filed March 24', 195.0

INVENTOR.

HTTO/P/VEX Patented Dec. 18, 1951 SELF-ADJU STING RECIRCULATING OVERFLOW James B. Crawford, Los Angeles, Calif., asslgnor to Paddock Pool Maintenance 00., Los Angeles, Calif., a corporation of California Application March 24, 1950, Serial No. 151,777

16 Claims. 1

This invention relates to apparatus for swimming pools, tanks and like receptacles, and more particularly to equipment for removing surface liquid in and on which scum, dust, leaves and other debris tends to gather to the detriment both of the appearance of the pool and of enjoyment of the users.

A principal object of the'invention is to provide novel surface skimming equipment which has improved means for regulation of the swimming rate.

Another object is to devise equipment of the described type consisting of a minimum number of parts which are of simple design and inexpensive to manufacture.

Another object is to provide apparatus which is easy to install and self-adjusting in operation.

Still another object is to provide for easy adjustment and control of the quantity and rate of removal of surface liquid.

Still other objects and advantages will be apparent from the detailed description which follows.

A present preferred embodiment of the present invention consists essentially of two parts, a float member and a fixed support which is connected to an outlet. The two parts have a telescoping relation with each other and together form an open chamber in which a quantity of the liquid in the pool or tank is segregated and separated from the main body of the liquid. This chamber will vary in size with changes in the depth of liquid in the pool which cause upward or downward movement of the float member. By withdrawing liquid continuously from the chamber a difierential in liquid levels of pool and chamber is created which aifects the buoyancy of the float member with the result that this member is caused to float below the liquid level of the pool but above the liquid level in the chamber. As a result a top layer of liquid spills over the top of the float member and into the chamber whence it is withdrawn by gravity or by a pump through the outlet connection to the fixed support. The fioat member automatically adjusts itself to the difference in liquid levels created by the withdrawal of liquid from the chamber.

In order to illustrate the invention and the manner of its use concrete embodiments thereof are shown in the accompanying drawings in which: 7

Figure 1 is a diagrammatic view partly in vertical section and partly in elevation of a portion of a swimming pool with a skimming device installed;

Figure 2 is a vertical sectional view on an enlarged scale through one form of skimming device during operation, the section being taken on the line 2-2 of Figure 3 with the outlet pipe shown in elevation;

Figure 3 is a plan, view on a reduced scale of the device shown in Figure 2; and

Figure 4 is a vertical sectional view similar to Figure 2 through a modification of the invention.

In Figure 1 is illustrated a typical installation of equipment of the present invention in a swimming pool, the surface water which is withdrawn being filtered and then returned to the pool. The skimming device indicated generally at A, and of either of the types illustrated in detail in the other figures of the drawing, is mounted on outlet pipe B at the edge of pool C. Outlet pipe has a hand-operated control valve D in advance of a pump E of any suitable or desired type, the discharge line F of the pump leading to a filter G of known or suitable type and thence by line 1-! back into the pool. When the withdrawn liquid is not recirculated, the pump E and filter G may be omitted and withdrawal efiected solely by gravity fiow.

Referring now to Figures 2 and 3 for a detailed showing of one form of the skimming device A, the latter comprises a chamber formed of but two parts 6 and 1 in telescoping relation with each other. Part 6 is a fixed member in the form of a plate or disk attached horizontally to the upturned open end of outlet pipe B at a' suitable distance below the level of the body of liquid in pool C. Mounted for vertical movement and enclosing fixed member 6 is float member I open at both ends but provided at its upper end with an internal sealed annular air chamber 8 formed by inner wall 9, bottom wall l0 and top wall ll. Bottom wall III will engage the upper face of plate 6 to act as a stop whenever the body of liquid in pool C is at or below the top 01. outlet pipe B. In the form shown plate 6 is circular and float member I is cylindrical but it is to be understood that these parts can be made in other shapes such as square, oval, triangular, etc. if desired. There is sufiicient clearance between the outer edge of plate 6 and the skirt or lower portion of float member 1 which telescopes therecver to permit free upward and downward movement of float member 1 as the liquid level a in the pool changes. When liquid is not being withdrawn by outlet pipe B, float member I rides or floats in the pool with its annular fiat top H well above the surface a, the two parts 6 and I cooperating to provide a chamber above plate 6 3 and enclosed by the portion of float member 1 above plate 8, this open chamber containing a body of liquid which is segregated from the main body in/pool C.

The device functions as follows: On opening valve D in outlet line B liquid will be withdrawn from the open chamber above plate 8 either by gravity or by the operation of pump E. The level of the liquid in the chamber will fall. This will automatically effect a change in the position of float member 1 relative to plate 8 since there is less liquid in the open chamber and hence a lower liquid level there. Member I will preforce move floats below the level a of the main body and surface liquid will pour over the top H and into the open chamber, member 1 finding a point of balance or equilibrium with the level of fluid in the open chamber at a position such as b (Figure 1) as compared with level a of the main body. It is usual practice to set the flow through outlet pipe B so that float member I adjusts itself with its top about A; of an inch below main liquid level a.

A low narrow upstanding annular flange or lip l2 may be provided at the outer edge of top H of float member 1. This has been found to have the further effect of enlarging (so to speak) the mouth or central opening in member 1 which admits the overflow liquid into the chamber above outlet pipe B, thereby increasing the draw of the device; in other words overflow begins at flange l2 instead of at the inner edge of top H as is the case when flange I2 is omitted. Flange or lip l2 may also be utilized to retain a flat screen (not shown) on the top of float member I to intercept and retain leaves and other debris which might clog pipe B or foul pump E.

Part 6 and I may be made of any suitable or desired material. Metals not subject to corrosion, such as copper and brass are suitable. The preferred materials, however, are plastic compounds such as certain of the well-known phenol-condensation products including Lucite, tenite, etc. Since there are no critical tolerances, part I as well as part 6 may be inexpensively molded of plastic such as Lucite which in addition to its inherent suitability also presents an attractive appearance. formed in two parts of equal size by a split mold operation and then integrally united to form the sealed float chamber 8.

Dimensions of the parts of the overflow or skimming device shown in Figures 2 and 3 for a typical installation are as follows: Plate or disc 6 is of Lucite plastic inch and 71%" in diameter. It is formed with flutes or depressions 6a on its upper face, as shown, to reduce weight. A central opening is drilled and tapped to screw on to the upturned vertical end of outlet pipe B. Float member I, also of Lucite plastic, has walls in thickness throughout. The internal diameter of the lower end or skirt which telescopes over plate 6 is 7%", providing clearance with plate 6. The reduced opening or mouth defined by air chamber 8 at the upper end has a diameter of 4%". The upstanding annular flange i2 is 3 2" in height. This size is adequate for most pools; for very large pools the dimen- Float member I may be initially 4 sions are increased or two devices of the specified size may be utilized advantageously.

Figure 4 shows a modification in which a substantially fluid tight seal is maintained between the plate and float members at certain depths of liquid in the pool but at lesser depths free access of fluid to outlet pipe B is permitted. In this form A, the fixed plate or disc member I is upwardly flared from a hub portion Ma which is threaded onto the upwardly directed end section of outlet pipe B, which section has a series of small openings in its side wall beneath a cap 26 which closes the top of the pipe, openings 25 being located above hub portion lid of plate or disc member I 8 but below a horizontal projection of the upper end of the latter. The outer edge of member I6 is recessed or otherwise arranged to receive and hold' a packing ring lib which bears against the telescoping lower skirt .portion of float member H to form a substantially fluid tight seal but the packing ring has a hard smooth outer surface which offers a minimum of frictional resistance to movement of float member ll. Toward its upper portion the skirt of fl lat member "is outwardly expanded in a smm th curve 21 into an enlarged offset which disposes its wall 28 out of contact with plate l8 and provides clearance around packing Ila. Above section 28 float member I! has an inwarlly extending annular sealed air chamber l8 formed by inner cylindrical wall is, bottom wall 20 and top wall 2|, In this form flat top 2| extends radially beyond chamber 18 and the cylindrical wall of member II. Top 2| may have a low, narrow upstanding flange or lip 22 around its edge.

The device of Figure 4 is made in a similar manner and operates similarly to the first form of the invention previously described except that when the main body of liquid falls to a predetermined level the descending movement of float member l1 brings the expanded outwardly curved wall 21 of the offset to and below packing lib on fixed plate iii, the liquid removed by pipe B is no longer conflned to that which spills over top 2! but will include liquid moving upwardly through the lower end portion of member 11 and around packing I61) and into the wide clearance space between the latter and wall 28 provided by the enlarged offset. Liquid will continue to pass in this manner through this lower passageway to outlet pipe B in unrestricted volume until level a of the main body has fallen to such an extent that bottom wall 20 of float chamber l8 comes to rest on the peripheral upper edge of fixed plate I6. As the pool is refilled to restore it to its original level, float member II will rise and sloping wall 21 will guide its lower skirt portion into telescoping relation again with plate l6. Cap 26 on the upper section of outlet pipe B and small outlet opening 25 will screen out leaves and large pieces of debris but a fine, mesh screen (not shown) seated on top 2| or surrounding the upper end ofskimming device A is still desirable in most instances.

- From the above it will be apparent that the equipment of the present invention for skimming and like operations is extremely simple both in or 11- is not more than one-eighth inch below the the system depends upon the rateat .which'the skimmed liquid is drawn offv by the circulation I Y pump, or by the drain" pipe in the case of a grav-' ity type outflow. Thisis in contrast to previously known skimming devices supportedbya float which floats entirely in the pool liquid, and the [position of whose overflow lip ishighly sensitive .to the buoyancy oi the float. Adjustment of such devices to skim at the desired rateis very I level of. the body of liqu'idiwhich is being skimmed. It will be seen' that the sensitivity of difiicult, while by contrast, the skimming rate of the presentdevice depends upontheliquidlever b maintained inside the device, and hencedk rectly upon the easily controll'ed rateoifoutflow throughpipe B.

1 The invention has been illustrated inl its appli cation to swimming polls but is directly useful generally wherever surfacelayers are to'be relm ovedfrom bodies of liquid/for any purpose and especially when this is to be done'with a mini-' mum of disturbance of lower layers ofliquid. By, utiliz ing a packing or seal between the flxedplate flii ai-id the floatingmember l1, seepage between these parts such as occurs between members 6 and i lbfli'igures 2 and 3, is'avoidedj as for the skim ,mingdevice of Figures ;4' an d 5, so long as the. I bodyof liquid is maintainedpata sufficiently hi h lev'eljjto ke'ep enlarged .joffs'et' ior flared] wall 211' above' plate; l6 (as in' 'F i'gure 4) only liquid' from' the surface can be withdrawn-through pip B I 7 5 While the invention ihas b'een hereinmsclosed ln-what iare now believed to be'pr'e'ierred ferment, it;- is to be understood "that; the invention is/not; l mited "to o the specific details thereof but co ersallichangfe fi: modific tio s and adap'tationswith in thescope of jthappended claims. 1 {I e1aim: I a; L' '1; v

j; r ,1.- In equipment for skimining swimming{poo' tanks and .the like. containing e bOdYQEOI liquid) ,thecombination or: sideandfbottom wall a ri ii hamberizp s J nearthesurface thereo andconstruclted and fd f iigel 1 1 11; vf-frorn teniain'jbod of mme se V ni e q ant t -of i u di eg eeated tionsfoi {the located said body of liquid s d am enwa l ide wall member id t work n I telescoped a open chamber,

chamber, .said member having a liquid overflow lip'fpositionedjnear the surface or the main body oirliquidand overwhich surface liquid from said main body; may ,spill into said chamber, float meansfoperatively connected to said movable wall and ar'ranged to;float in the liquid contained inside saidf chamber, whereby said over-flow lip will rise 'and ifall with the liquid level inside said chambenjan outflowconduit for removing liquid ,from'said chamben and a circulation pump connecte'd ween outflow conduit.

'j 3-. skimming device for pools, tanks and the fllke comprising aflxedly supported circular plate, a ,cylindrical-.membergtelescoped over said plate with aslidable fit :gin'g an air chamb' v agl a stopf'to engage the latter to limit the downwardjmovement of said member, the top wall of v said chamber forming an annular'flat top for said member] over which liquid will flow intothe open chamberabove said plate formed by said cylind i lx I 'chamberjis'lowered' by withdrawing fluid from said open chamber, and an outflow conduit for jme 'son said member providv'e said plate and serving ember when; the liquid level in said open removing liquid from said chamber.

41A skimmingqdevice for pools, tanks and the like-comprising a fixedly supported circular plate,

flat a'nn'ular top, a low flange extending above 'said top around the edge thereof,;a'nd an outflow I conduit for removing liquid from said chamber.

5. 'fA skimming device for. pools,,tanks and the a e compr is in g a, fixedly supported horizontally et.

disposed plateafloat member open atboth ends having a 'skirts'jportion' in telescoping relation with'said plate I and a sealed air chamber above saideplate,"said) float member and said plate co- -,9perating td provide.aniop en chamber for seggregalting ai guanltfity of liquid in t he pool from the frnain body of liquid, said air, chamber being within said open chamber so as to float in the iqiiid contained th'erewithin, said float member hav' g ,afiat top which projects beyond hereof over which liquid from the flow-intoflsaid openchamber when depressed by'withdrawal of liqmsa ,openphaniber, and an outflow conern vingfliqui'ci from; said chamber. mining device for pools, tanks and the rising a 'flxe'dly supportedhorizontally circular plate, la cylindrical floatineint foth gends havingjits lower portion said plate for'vertical movement he toand having'a sealed air champlate, said float member and said chamber open at the top to hold ty of the liquid in the pool separate from ome nee therewithin, fsaid float g. a flat annular jtop'which extends ,tic'alwalls thereof, over which top aid cl'iamber. v

skimmingdevicefifor pools, tanks and the e inainbody of liquid, saidair chamber being 4 within said open chamber so as to float.

and arrbutflow fcond uit fonremoving liquid from J.

in isin a fixedly. supported circular plate,

a cylindrical float member having a skirt telescoped over said plate with a close sliding lit to form with said plate a chamber open at the top for segregating a quantity of liquid from the main body of liquid in the pool, float means within the oonflnes of said member above said plate, said member having an annular flat topover which liquid from the main body flows into said chamber where said member moves downwardly beneath the level of the main body of liquid in response to withdrawal of liquid from said open chamber, said member having an enlarging ofl'est intermediate its ends to permit liquid to by-pass said plate and enter said chamber from beneath when the main body 01 liquid falls to a predetermined level, and an outflow conduit for removing liquid from said chamber.

8. A skimming device for pools, tanks and the like comprising in combination a circular plate having a packing'ring on its outer edge, and a cylindrical member open at both ends having a skirt portion to telescope over said plate and to slidably engage said packing ring to make a fluid tight seal, a float inside and connected to said cylindrical member, said member having an enlarged oifset portion to permit liquid to by-pass said plate in certain positions of said member relative to said plate, and an outflow conduit for removing liquid from said chamber.

9. A skimming device for pools, tanks and the like comprising in combination a circular plate having a packing ring on its outer edge, and a cylindricalmember open at both ends having a skirt portion to telescope over said plate and to slidably engage said packing ring to make a fluid tight seal, a float inside and connected to said cylindrical member, said member having an enlarged oiIset portion to permit liquid to by-pass said plate in certain positions of said member relative to said plate, said ofiset portion of said member joining said skirt portion thereof in a smooth curve to permit free movement of said member into and out of fluid tight sealing engagement with said plate, and an outflow conduit for removing liquid from said chamber.

10. In skimming equipment for swimming pools, tanks and the like the combination with a vertical outlet pipe of an upwardly dished plate mounted on said pipe, said plate having a packing ring on its outer edge, an open-ended float member having a skirt portion telescoped over said plate to engage said packing ring and form a fluid tight seal, float means on the upper portion 01. said member to engage said plate as a stop to limit the downward movement of said member on said plate, means on said member providing a by-pass for fluid around said plate as said member approaches the lower limit of its movement.

11. In skimming equipment for swimming pools, tanks and the like the combination with a vertical outlet pipe of an upwardly dished plate mounted on said pipe, said plate having a packing ring on its outer edge, an open-ended float member having a skirt portion telescoped over said plate to engage said packing ring and form a fluid tight seal, float means on the upper portion of said member to engage said plate as a stop to limit the downward movement of said member on said plate, means on said member providing a bypass for fluid around said plate as said'member approaches the lower limit of its movement, said pipe having a closed end and ports in its side wall above said plate but below a horizontal Drojection of its upper end.

12. In equipment for skimming swimming pools, tanks and the like the combination of a circular palte mounted horizontally beneath the surface of a body of liquid, and a cylindrical float member supported by the liquid in telescoping relation with said plate, said member having an air chamber partially closing the upper end thereof, said float member and said plate forming a chamber in which a quantity of liquid is separated from the main body of liquid, and means for withdrawing liquid from said chamber automatically to depress said float member relative to said plate and to cause liquid from the main body to overflow said member into said chamber.

13. In equipment for skimming swimming pools, tanks and the like containing a body of liquid, the combination of: a chamber positioned in said body of liquid near the surface thereof and constructed and arranged to hold a quantity of liquid segregated from the main body of liquid, said chamber being partly deflned by fixedly mounted wall means and partly deflned by a vertically movable side wall structure having an overflow portion over which liquid from the main body can spill into said chamber when said overflow portion is lowered below the level of said main body, and float means operatively connected to said movable side wall structure and arranged to float in the liquid inside said chamber, whereby said overflow portion of said side wall structure will rise and fall with the liquid level inside said chamber, and an outlet for removing liquid from said chamber.

14. A skimming device for pools, tanks and the like comprising a. fixedly supported horizontally disposed plate, a float member open at both ends having a skirt portion in telescoping relation with said plate and a sealed air chamber above said plate, said float member and said plate cooperating to provide an open chamber for segregating a quantity of liquid in the pool from the main body of liquid, said air chamber being located within said open chamber so as to float in the liquid contained therewithin, said float member having an overflow edge over which liquid from the main body will flow into said open chamber when said member is depressed by withdrawal of liquid from said open chamber, and an outflow conduit for removing liquid from said chamber.

15. In equipment for .skimming swimming pools, tanks and the like containing a body of liquid, the combination of: an open chamber comprising a fixedly supported bottom wall structure, a side wall structure surrounding said bottom wall structure and movable vertically relative to said bottom wall structure in sliding engagement with the periphery thereof, said chamber having an overflow portion over which liquid from the main body can spill into said chamber when said overflow portion is lowered below the level of said main body by withdrawal of liquid from said chamber, a float included in the chamber located inside the chamber and operatively connected to said side wall structure, so as to float in the liquid contained inside the chamber, whereby said overflow portion of the chamber rises and falls with the liquid level inside the chamber, and an outlet for removing liquid from said chamber.

I 16. In equipment for skimming swimming pools, tanks and the like containing a body of liquid, the combination of: an open chamber comprising a fixedly supported bottom wall structure, a side wall structure surrounding said bottom wall structure and movable vertically relative to said bottom wall structure in sliding engagement with the periphery thereof, an over flow lip on said side wall structure over which liquid from the main body can spill into the chamber when said overflow lip is lowered below the level oi said main body by withdrawal of liquid from said chamber, a float fixedly connected to the side wall structure and arranged inside ber, whereby the said overflow lip rises and falls with the liquid level inside the chamber, and an outlet for removing liquid from said chamber. JAMES B. CRAWFORD.

REFERENCES CITED file of this patent:

Number UNITED STATES PATENTS Name Date Carlisle Aug. 12, 1902 Post ..1 Jan. 31, 1905

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