Tank with automatic fill and overfill drain

Abstract

Apparatus for adjusting and maintaining the level of water in a swimming pool. The apparatus includes a tank in communication with the pool and fill and drain devices mounted in the tank for select elevational adjustment. The devices are coupled whereby elevational adjustment of one of the devices functions to simultaneously adjust the elevation of the other of the devices.

Description

This is a continuation-in-part of U.S. application Ser. No. 10/079,014, filed Feb. 19, 2002 by Andrew L. Pansini, the inventor herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an automatic fill water level control device and an overfill drain device for use with a swimming pool to obtain a desired pool water level. More specifically, the invention relates to a tank that is in communication with a pool and contains an adjustable automatic fill device and an overfill drain device mounted for movement together, so that setting the level of one of the devices automatically sets the level of the other device.

2. Related Art

Conventional pools contain overfill drains constructed as follows. A drain pipe is placed in the pool wall at the height of the desired water level. The drain pipe terminates either on the land surrounding the pool or into a nearby drain. Leaves and other debris floating on the pool water surface can plug the outlet hole in the pool wall, compromising the efficiency of the overfill drain.

U.S. Pat. No. 4,621,657 discloses a monitoring system for a swimming pool including a chamber in communication with the pool, adjustable fill means for determining a desired water level for the pool, and an overflow pipe for draining water from the chamber when the water level in the chamber exceeds the desired pool water level. The overflow pipe does not move with the automatic fill means. One must first set the automatic fill means then secondly adjust the overfill drain to be just slightly higher than the water level set by the automatic fill means.

Accordingly, it is desirable to provide a device containing an adjustable automatic fill device and an adjustable overfill drain device that can be simultaneously adjusted to determine and adjust the desired water level in a pool.

SUMMARY OF THE INVENTION

The invention is directed to a device for adjusting the water level in a swimming pool including a tank that is in communication with the pool and contains an automatic fill device and an overfill drain device mounted for movement together so that the height of both devices may be simultaneously adjusted to obtain a desired water level in the pool.

Other objects, features and advantages of the present invention will be apparent to those skilled in the art upon a reading of this specification including the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is better understood by reading the following Detailed Description of the Preferred Embodiments with reference to the accompanying drawing figures, in which like reference numerals refer to like elements throughout, and in which:

FIG. 1 is a cross-sectional elevational view of a conventional skimmer tank and the inventive device.

FIG. 2 is a top plan view of a first embodiment the inventive device.

FIG. 3 is a side view of the overflow means of the first embodiment inventive device.

FIG. 4 is a side view of the overflow means of the first embodiment inventive device.

FIG. 5 is a side view of the automatic fill means of the first embodiment inventive device.

FIG. 6 is a side view of the adjusting means of the first embodiment inventive device.

FIG. 7 is a cross-sectional elevational view, with parts thereof broken away, of a second embodiment of the inventive device, installed in place adjacent a swimming pool.

FIG. 8 is a perspective view of the second embodiment of the inventive device, with parts thereof broken away.

FIGS. 9A and 9B are cross-sectional elevational views of the second embodiment device, illustrating the device in different conditions of elevational adjustment.

FIG. 10A is a cross-sectional elevational view of a third embodiment of the inventive device.

FIG. 10B is a plan view of the arm used in the third embodiment device to secure the overflow drain device and the fill device together for unitary elevational adjustment.

FIG. 11 is a cross-sectional elevational view, with parts thereof broken away, illustrating a fourth embodiment of the inventive device.

FIG. 12A is a cross-sectional elevational view, with parts thereof broken away, illustrating a fifth embodiment of the inventive device.

FIG. 12B is a plan view of the follower used in the fifth embodiment device to secure the overflow drain device and the fill device together for unitary elevational adjustment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In describing preferred embodiments of the present invention illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the invention is not intended to be limited to the specific terminology so selected, and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner to accomplish a similar purpose.

FIRST EMBODIMENT

FIGS. 2-6

The first embodiment inventive device, designated device 10, includes a tank 12 that is in communication with a pool 18 via an equalizer line 16. Tank 12 is a relatively no flow chamber, and the water level in tank 12 is equal to the water level in pool 18. Tank 12 contains an automatic fill device 20 and an overfill drain device 60. Automatic fill device 20 allows water to enter the tank 12 and pool 18 when the water level of tank 12 and pool 18 reaches a preselected lower level. Overfill drain device 60 allows water to drain out of tank 12 and pool 16 when the water level of tank 12 and pool 16 reaches a level higher than that set by the automatic fill device. This would occur during a rainstorm. As described in detail below, automatic fill device 20 and overfill drain device 60 are in fixed relation to each other within tank 12, so that the height of both devices can be simultaneously adjusted to obtain a desired water level in the pool. Setting the height of one of the devices automatically sets the height of the other device.

As illustrated in FIG. 1, device 10 is preferably located adjacent to a conventional circular skimmer tank 100 which is in communication with pool 18 via passageway 104. A conventional skimmer weir 120 is hingedly connected to floor 110 of passageway 104 at the entrance to pool 18. Skimmer tank 100 also includes a skimmer basket 122 for retaining leaves and debris that are drawn into skimmer tank, and a drain pipe 124.

Equalizer line 16 connects tank 12 (a relatively no flow chamber) to passageway 104 of skimmer tank 100 (a positive pressure area) so that tank 12 is in communication with pool 18 and the water level in tank 12 is equal to that in pool 18. A filter screen 112 is preferably provided over the opening 16a of equalizer line 16 to prevent leaves and debris from clogging equalizer line 16 and from entering tank 12 and clogging overfill drain device 60. During operation, filter screen 112 is back flushed every time automatic fill device 20 is activated to allow water to enter tank 12.

As illustrated in FIG. 2, tank 12 has first, second, third and fourth sides 12a, 12b, 12c, 12d. Side 12c has wall connectors (not shown) for incoming and outgoing water. First side 12a is preferably concave, and configured so that first side 12a fits adjacent to the convex outer surface of circular skimmer tank 100. Locating device 10 adjacent skimmer tank 100 allows for easy access to device 10. Tank 12 may have a lid 13, or may be formed as part of skimmer tank 100 and share a common lid with skimmer tank 100.

Tank 12 contains automatic fill device 20 and overfill drain device 60 in a fixed relationship to each other. This can be accomplished by numerous designs in which automatic fill device 20 and overfill drain device 60 are connected to each other so that their height within tank 12 can be simultaneously adjusted.

By way of illustration and for exemplary purposes only, automatic fill device 20 and overfill drain device 60 can be mounted on a support member in the form of an adjustable plate 80, so that the height of automatic fill device 20 and overfill drain device 60 can be simultaneously adjusted via plate 80. First and second protrusions 14a, 14b extend vertically outwardly from first and second sides 12a, 12b of tank 12 to slidably receive a portion of plate 80 and act as guide means for adjusting the height of plate 80, as follows. First and second ends 80a, 80b of plate 80 are slidably inserted between fourth side 12d of tank 12 and first and second protrusions 14a, 14b. The protrusions 14a, 14b provide channels which slidably receive the plate 80. The plate provides means for mounting the automatic fill device 20 and overfill drain device 60 in fixed relationship to each other for unitary simultaneous elevational movement relative to the chamber provided by the tank 12. During such movement, the plate slides vertically within the channels provided by the protrusions 14a, 14b. Plate 80 is held in place against fourth side 12d of tank 12 by adjusting means 84. To adjust the desired pool level, the heights of automatic fill device 20 and overfill drain device 60 are simultaneously adjusted by backing off adjusting means 84, moving plate 80 to a desired position within tank 12 and engaging adjusting means 84 to lock and hold plate 80 in place in the desired position.

Adjusting means 84 may be a knob 86 attached to a screw 88 that extends through a threaded hole in plate 80, as illustrated in FIGS. 2 and 6. Plate 80 is held at a desired height in tank 12 by turning knob 86 in a first direction so that end 88a of screw 88 engages fourth side 12d of tank 12. To adjust the desired pool level, the height of automatic fill device 20 and overfill drain device 60 is simultaneously adjusted by turning knob 86 in a second direction to disengage end 88a of screw 88 from fourth side 12d of tank 12, sliding plate 80 vertically upward or downward to a desired pool water level, and turning knob 86 in the first direction to engage end 88a of screw 88 against fourth side 12d of tank 12.

Adjusting means 84 can be any other means suitable for adjusting the height of plate 80 and locking it in a desired position within tank 12. For example, one might utilize a threaded rod vertically attached to a common member of plate 80. The rod would have a knob on the top end, and by swivel means be held to the floor of the tank. Turning the knob in one direction raises the device, and turning the knob in the other direction lowers the device. Although the drawings show plate 80 in a vertical plane, it is to be understood that plate 80 could be guided in a horizontal plane, with mechanical means for raising, lowering and locking the device.

Automatic fill device 20 allows water to enter tank 12 and pool 18 (via equalizer line 16) when the water level in tank 12 and pool 18 falls below a set level. As illustrated in FIGS. 2 and 5, automatic fill device 20 includes a float valve 22 having a float arm 24 with first and second ends 24a, 24b, a conventional valve 26 attached to first end 24a and a float ball 28 attached to second end 24b. Float ball 28 floats at the surface of the water in tank 12. A stop arm 30 is attached at its first end 30a to valve 26. Stop arm 30 may be attached to valve 26 by fasteners 32, such as screws, or any other suitable means. Second end 30b of stop arm 30 is engaged with float arm 24 when the water in tank 12 is at a higher level than desired, such as in a rain storm. Stopping the float arm 24 in the horizontal position prevents the valve 26 from adding still more water to the pool 18.

Valve 26 is connected to first end 40a of vertically oriented pipe 40. Second end 40b of vertically oriented pipe 40 is connected to first end 42a of elbow-shaped connector pipe 42. Second end 42b of connector pipe 42 is attached to a water source (not shown) that is external to tank 12.

Valve 26 is closed when second end 30b of stop arm 30 is engaged with float arm 24. When the water level in tank 12 drops and falls below the preselected level, float arm 24 rocks the seal of valve 26, thereby breaking the seal, opening valve 26 and allowing water from the external water source (not shown) to move through connector pipe 42, up through vertically oriented pipe 40 and out valve 26 into tank 12.

During heavy rain conditions when the water level in tank 12 and pool 18 rises above the preselected water level, stop arm 30 prevents float arm 24 from rising with the water above the preselected level, thereby preventing float arm 24 from opening float valve 26 and allowing water to enter tank 12. This prevents automatic fill device 20 from counteracting the drainage action of overfill drain device 60 during heavy rain conditions.

Overfill drain device 60 allows excess water to drain out of tank 12 and pool 18 when the water level is higher than the preselected water level set by adjusting the height of automatic fill device 20 and overfill drain device 60 in tank 12 via plate 80. As illustrated in FIGS. 3 and 4, overfill drain device 60 includes a vertically oriented hollow pipe attached to adjustable plate 80. First end 62a of pipe 62 is open, forming an inlet. Second end 62b of pipe 62 is attached to first end 64a of elbow pipe connector 64. Second end 64b of elbow pipe connector 64 is attached to first end 70a of hose 70. Second end 70b of hose 70 is connected to overfill drain pipe 72 which passes through outlet 74 formed in tank 12. Clamps 68 may be used to securely connect first end 70a of hose 70 to second end 64b of elbow connection pipe 64 and second end 70b of hose 70 to overfill drain pipe 72. Hose 70 may be looped, as illustrated in FIG. 3, so that it can flex with the movement of plate 80 if a new water level is selected.

The desired water level is selected by the following method: providing a tank 12 that is in communication with pool 18 and that contains automatic fill device 20 and overfill drain device 60 in fixed relation to each other, wherein elevational movement of the automatic fill device 20 and overfill drain device 60 relative to tank 12 is not restricted by any attachment to tank 12, the heights of the automatic fill device 20 and overfill drain device 60 within the tank are adjustable and setting the height of one of the devices in the tank automatically sets the height of the other device in the tank and simultaneously adjusting the height of automatic fill device 20 and overfill drain device 60 within tank 12 via plate 80 so that the valve 26 will be at the desired water level. Float ball 28 is preferably weighted so that it rides half out of the water and half under water. This keeps the float arm 24 in a horizontal position on the surface of the water when the valve 26 is closed. When the water level in tank 12 rises above the preselected water level, such as during a rain storm, the excess water drains out of tank 12 and pool 18 through first end 62a, pipe 62, elbow pipe connector 64, hose 70, overfill drain pipe 72 and out outlet 74 to the surrounding ground or a drain located outside of tank 12.

Locating outlet 74 for overfill drain device 60 outside of pool 18 avoids the problem of leaves and debris from the pool clogging the outlet, and eliminates the necessity of providing a separate pipe through the pool wall for overfill drain device 60. It is to be understood that automatic fill device 20 is connected to an outside water source by a hose as shown in FIG. 3 for the overfill drain.

SECOND EMBODIMENT

FIGS. 7-9B

This embodiment, designated 130, includes a tank 132 connected in fluid communication with a pool by means of a conduit 134 whereby the level of water in the pool and the tank is equalized, as may be seen by the dashed line 136. As shown in FIG. 7, the pool has a sidewall 138 through which the conduit 134 extends, and a deck 140. The top of the tank 132 is closed by a removable cover 142. A drain conduit 146 and water supply conduit 148 extend through the bottom wall 150 of the tank.

Interiorly, the tank 132 is provided with an overflow drain device 152 connected in sealed fluid communication with the drain conduit 146 and a fill device 154 connected in sealed fluid communication with the supply conduit 148.

The fill device 154 comprises: a vertically extending rigid conduit 156; an annular float 158 slidably received on the conduit 156; and a valve mechanism 160 secured over the top of the conduit 156. The valve mechanism closes the top of the conduit 156 and is operated by an arm 162 forming part of the mechanism and extending laterally therefrom. The arm 162 is connected to the float 158 by a rod 166 through means of a connector 168 carried by the float. A water discharge conduit 170 extends laterally from the valve mechanism. In use, when water within the tank 132 is low, the float pulls the valve mechanism arm 162 downwardly to open the valve mechanism and discharge water into the tank. When water in the tank raises the float sufficiently, the arm 162 is moved upwardly to close the valve mechanism 160 and terminate the flow of water from the conduit 170.

FIG. 9A illustrates how the fill device 154 is secured in place within the tank 132. As there seen, a connection conduit 148A forming part of the supply conduit 148 is secured to an extends through the bottom wall 150 of the tank. The upper end of the conduit 148A extends slidably into the conduit 156. An O-ring 172 establishes a sealed slidable connection between the conduits 148A and 165. As a result of this sealed connection, the pressurized water entering the conduit 148 functions to move the conduit 156 and the mechanism carried thereby upwardly. This movement can be seen by a comparison of FIGS. 9A and 9B.

The construction and mode of operation of the overflow drain device 152 may also be seen from FIGS. 9A and 9B. As there shown, it will seen that the device comprises the rigid outer conduit 174 secured to the drain conduit 146 in fixed relationship to the bottom wall 150 of the tank. The outer conduit 174 threadably receives a rigid inner conduit 176 having a drain opening 178 extending therethrough. The top of the inner conduit 176 is closed by a cap 180 fixed thereto. The cap is formed an annular stop disk 182 extending laterally therefrom for engagement with the top of the valve mechanism 160.

Interiorly, the conduit 174 is formed with screw threads 184 for threaded engagement with complimental external threads formed on the conduit 176. Through these threads, the elevation of the conduit 176 may be adjusted by turning the conduit 176 about its longitudinal axis. Such adjustment, between lower and upper extremities, may be seen by a comparison of FIGS. 9A and 9B. An O-ring 186 carried by the inner conduit 176 maintains sealed connection between the conduits 174 and 176 as they are elevationally adjusted.

The top surface of the valve mechanism 160 serves as a follower which engages the disk 182 to stop and limit extension of the conduit 156 in response to pressure of the water being supplied thereto. A flanged opening 188 formed in the bottom wall 150 provides for connection of the conduit 134 to the tank 132. The dashed lines 136 depicted in FIGS. 9A and 9B illustrate the water level established by the apparatus, as the apparatus is adjusted between the lower and upper extremities depicted in these figures.

THIRD EMBODIMENT

FIGS. 10A-10B

This embodiment is similar to the second embodiment, except that the conduit 156 is not free to rise in response to fluid pressure from the water supply conduit 148. Rather the conduit 156 is held by connection to a lifting arm 190 secured to the inner conduit 176. The arm 190 provides collars 192 and 194 extending, respectively, around the conduits 156 and 176. A set screw 196 secures the collar 192 against movement relative to the conduit 156. Annular shoulder elements 198 and 200 are secured to the conduit 176 to either side of the collar 194 to permit the conduit 176 to be turned about its axis relative to the arm 190. Water level adjustment of the third embodiment apparatus is provided by simply turning the inner conduit 176 to screw it into and out of the conduit 174. A modified cap 180a provides a convenient flange which may gripped for this purpose.

FOURTH EMBODIMENT

FIG. 11

This embodiment is also similar to the second embodiment, except that the conduit 156 is not free to rise in response to fluid pressure from the water supply conduit 148. Rather, the conduit 156 is held from extension by a follower 202 fixed to the top of the valve mechanism 160 and engaged between the disk-shaped flanges 204, 206 of a wheel 208 concentrically fixed to the conduit 176. A cap 180b is secured to the conduit 176 above the wheel 208 and serves as a knob whereby the conduit 176 may be turned into and out of the conduit 174 to adjust the height of the drain opening 178. Such adjustment of the conduit 176 is imparted to the conduit 156 of the fill device 154 through means of engagement of the flanges 204, 206 with the follower 202. Thus, water adjustment in the fourth embodiment is provided by simply turning the conduit 176 to screw it into or out of the conduit 174.

FIFTH EMBODIMENT

FIGS. 12A-12B

This embodiment is similar to the third embodiment, except that a separate vertically extending screw 210 is provided for vertical adjustment of the fill and overflow devices and that outer and inner conduits 174a and 176a, respectively, of the drain device 152a are free to telescopically move relative to one another (i.e. there is no screw threaded connection between the conduits 174a and 176a). An O-ring 186 establishes sealed connection between the conduits 174a and 176a, while permitting their free telescopic movement. The top of the conduit 174a is closed by a cap 212.

The construction of the fill device 154 corresponds to that of the third embodiment. Thus, in the fifth embodiment, both the drain device 152a and the fill device 154 are free to telescopically move up and down.

Water level adjustment in the fifth embodiment is provided through means of the screw 210 and a follower 214 having a screw threaded opening 216 threadably received on the screw 210. The follower extends transversely of the tank and is formed with openings 218 and 220 which provide collars received around the conduits 176a and 156, respectively. Set screws 222 are threadably received in the follower and extend into the openings 218 and 220 to secure engagement with the conduits 156 and 176a. Thus, elevational adjustment of the follower 214 in response to turning of the screw 210 is imparted directly to the conduits.

The ends of the follower 214 are formed with open vertically extending notches 224. These notches are complimental to and slidably received around vertically extending guide members 226 fixed to the interior of the tank 132. This is assures smooth movement of the follower 214 in response turning of the screw 210.

The lower end of the screw 210 is rotatably received within a complimental recess 228 formed in the bottom wall 150. The upper end of the screw 210 has an annular knob 130 fixed thereto to enable the screw to be manually turned about its vertical axis. A rod 232 extends across the top of the tank and bears against the knob 230 to restrain the screw 210 against vertical movement. One end of the rod 232 is received within a recess 234 formed in the interior wall of the tank 132. The other end of the rod is engaged beneath a cleat 236 fixed to the interior wall of the tank 132 at a location diametrically opposite the recess 232. The rod 232 is narrow, as compared to the diameter of the knob 230 to enable to the knob to be easily gripped and turned for adjustment. For servicing of the components to the interior of the tank, the rod may be disengaged from the cleat 236 to enable the rod to be removed.

CONCLUSION

While the level control valves used in the devices of the present invention have been shown as being of the float controlled type, other common valves, such as the diagram valves used in toilet tanks, may be employed in place of the float controlled valves. This is but one of the variations which might be employed, without departing from the invention. Other modifications and variations of the present invention are also possible, as will be appreciated by those skilled in the art in light of the above teachings. For example, tank 12 may be formed as part of skimmer tank 100, automatic fill device 20 and overfill drain device 60 can be connected in fixed relation to each other by any conventional means, and adjusting means 84 can be any suitable means for adjusting the height of automatic fill device 20 and overfill drain device 60. It is therefore to be understood that, within the scope of the appended claims and their equivalents, the invention may be practiced otherwise than as specifically described.

Claims

1. A tank in communication with a swimming pool, said tank containing an automatic fill device and an overflow drain device; means mounting the fill device and drain device within the tank for unitary elevational adjustment to simultaneously adjust the height of the devices relative to the tank to obtain a desired water level in the pool.

2. A tank according to claim 1, wherein the fill and drain devices are separate and the means mounting the devices within the tank comprises:

a. a support mounting the drain device to the tank for vertical movement to enable the elevation of the drain device relative to the tank to be selectively adjusted; and,

b. a connection between the drain device and fill device to elevationally move the fill device responsive to elevational adjustment of the drain device.

3. A tank according to claim 2 wherein the support comprises a screw connection between the tank and the drain device.

4. A tank according to claim 2 wherein:

a. the fill device is connected to a source of water under pressure and the mounting means secures the fill device for vertical extension relative to the tank in response to the pressure; and,

b. the connection comprises a stop carried by the drain device for engagement with the fill device to limit extension of the fill device.

5. A tank according to claim 2 wherein:

a. the mounting means secures the fill device for slidable vertical movement relative to the tank; and,

b. the connection moves the fill device vertically responsive to elevational adjustment of the drain device.

6. A tank according to claim 5 wherein the connection comprises:

a. an arm secured to the drain device for vertical movement therewith; and,

b. a collar on the arm engaged with the fill device to impart vertical movement of the drain device to the fill device.

7. A tank according to claim 5 wherein the connection comprises:

a. a disc carried by and extending around the drain device; and,

b. a follower carried by the fill device and extending therefrom into engagement with the disc to impart vertical movement of the drain device to the fill device.

8. A tank according to claim 1 wherein the means comprises:

a. screw mounted within the tank for rotation about a generally vertically extending axis; and,

b. a follower threadably engaged with the screw for vertical movement relative to the tank in response to rotation of the screw about the axis, said follower being connected to the fill and overflow devices to move the devices vertically with the follower.

9. A tank according to claim 8 wherein the follower extends transversely of the tank and the tank further comprises a vertically extending guide member slidably engaged with the follower to guide the follower for vertical movement in response to rotation of the screw.

10. Apparatus for adjusting and automatically maintaining a predetermined water level within a swimming pool, said apparatus comprising:

a. a tank communicating with the pool whereby the water level within the tank is the same as that of the pool;

b. a fill valve device mounted within the tank for elevational movement relative thereto;

c. an overflow drain device mounted within the tank for elevational movement relative thereto; and,

d. means to selectively adjust the elevation of one of the devices within the tank and impart a corresponding elevational adjustment to the other of the devices.

11. Apparatus according to claim 10, wherein the means comprises:

a. a support mounting the drain device for vertical movement to enable the elevation of the drain device relative to the tank to be selectively adjusted; and,

b. a connection between the drain device and fill valve device to elevationally move the fill valve device responsive to elevational adjustment of the drain device.

12. Apparatus according to claim 11 wherein the support comprises a screw connection between the tank and the drain device.

13. Apparatus according to claim 11 wherein:

a. the fill device is connected to a source of water under pressure and the mounted for vertical extension relative to the tank in response to the pressure; and,

b. the connection comprises a stop carried by the drain device for engagement with the fill device to limit extension of the fill device.

14. Apparatus according to claim 11 wherein:

a. the fill device is mounted for slidable vertical movement relative to the tank; and,

b. the connection moves the fill device vertically responsive to elevational adjustment of the drain device.

15. Apparatus according to claim 15 wherein the connection comprises:

a. an arm secured to the drain device for vertical movement therewith; and,

b. a collar on the arm engaged with the fill device to impart vertical movement of the drain device to the fill device.

16. Apparatus according to claim 14 wherein the connection comprises:

a. a disc carried by and extending around the drain device; and,

b. a follower carried by the fill device and extending therefrom into engagement with the disc to impart vertical movement of the drain device to the fill device.

17. A tank according to claim 10 wherein the means comprises:

a. a screw mounted within the tank for rotation about a generally vertically extending axis; and,

b. a follower threadably engaged with the screw for vertical movement relative to the tank in response to rotation of the screw about the axis, said follower being connected to the fill and overflow devices to move the devices vertically with the follower.

18. A tank according to claim 17 wherein the follower extends transversely of the tank and the tank further comprises a vertically extending guide member slidably engaged with the follower to guide the follower for vertical movement in response to rotation of the screw.

19. Apparatus for adjusting and automatically maintaining a predetermined water level within a swimming pool, said apparatus comprising:

a. a tank communicating with the pool whereby the water level within the tank is the same as that of the pool;

b. a fill valve device mounted within the tank for elevational movement relative thereto;

c. an overflow drain device mounted within the tank for elevational movement relative thereto;

d. a screw securing the drain device to the tank whereby turning of the drain device selectively adjusts the elevation of the drain device relative to the tank; and,

e. a connection between the drain device and fill device to elevationally move the fill device responsive to elevational adjustment of the drain device.

20. Apparatus according to claim 19 wherein:

a. the fill device is connected to a source of water under pressure and the mounted for vertical extension relative to the tank in response to the pressure; and,

b. the connection comprises a stop carried by the drain device for engagement with the fill device to limit extension of the fill device.

21. Apparatus according to claim 19 wherein:

a. the fill device is mounted for slidable vertical movement relative to the tank; and,

b. the connection moves the fill device vertically responsive to elevational adjustment of the drain device.

22. Apparatus according to claim 21 wherein the connection comprises:

a. an arm secured to the drain device for vertical movement therewith; and,

b. a collar on the arm engaged with the fill device to impart vertical movement of the drain device to the fill device.

23. Apparatus according to claim 21 wherein the connection comprises:

a. a disc carried by and extending around the drain device; and,

b. a follower carried by the fill device and extending therefrom into engagement with the disc to impart vertical movement of the drain device to the fill device.

24. Apparatus for adjusting and automatically maintaining a predetermined water level within a swimming pool, said apparatus comprising:

a. a tank communicating with the pool whereby the water level within the tank is the same as that of the pool;

b. a fill valve device mounted within the tank for elevational movement relative thereto;

c. an overflow drain device mounted within the tank for elevational movement relative thereto;

d. a screw mounted within the tank for rotation about a generally vertically extending axis; and,

e. a follower threadably engaged with the screw for vertical movement relative to the tank in response to rotation of the screw about the axis, said follower being connected to the fill valve and overflow devices to move the devices vertically with the follower.

25. A tank according to claim 24 wherein the follower extends transversely of the tank and the tank further comprises a vertically extending guide member slidably engaged with the follower to guide the follower for vertical movement in response to rotation of the screw.