U.S. patent number 3,739,405 [Application Number 05/223,861] was granted by the patent office on 1973-06-19 for water level maintenance device for swimming pools.
Invention is credited to Clinton R. Schmidt.
United States Patent |
3,739,405 |
Schmidt |
June 19, 1973 |
WATER LEVEL MAINTENANCE DEVICE FOR SWIMMING POOLS
Abstract
A device for maintaining the water in a swimming pool at an
established level, is disclosed. The subject device involves a
water-level tank which has a fluid connection to the swimming pool
such that water in both the water-level tank and the swimming pool
are at the same level. A double-pole float switch is mounted within
the water-level tank to continually sense the water level therein.
Whenever the water level is below a selected fill level, the float
switch activates an electrical solenoid valve which permits water
to be added to the pool. Whenever the water level is above a
selected level, the double-pole float switch operates to energize a
drain pump which extracts water from the pool until the established
water level is attained.
Inventors: |
Schmidt; Clinton R. (Glendale,
CA) |
Family
ID: |
22838258 |
Appl.
No.: |
05/223,861 |
Filed: |
February 7, 1972 |
Current U.S.
Class: |
4/508; 137/428;
137/412 |
Current CPC
Class: |
E04H
4/12 (20130101); Y10T 137/7368 (20150401); Y10T
137/742 (20150401) |
Current International
Class: |
E04H
4/12 (20060101); E04H 4/00 (20060101); E04h
003/16 (); E04h 003/18 () |
Field of
Search: |
;4/172,172.17,172.15
;137/412,428 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Artis; Henry K.
Claims
What is claimed is:
1. In a water-level control system for swimming pools, a tank for
containing a portion of the pool water such that the pool water in
both the pool and tank are at the same level, the tank
including:
a body formed by a closed upright wall and a floor, said pool water
being contained in said body;
an aperture situated in the floor of said body through which pool
water is permitted to enter said body;
a deck flange positioned to be received by the uppermost portion of
said closed upright wall of said body, said deck flange serving to
extend said upright wall and having a telescoping relationship
therewith, said deck flange including a hollow cylindrical portion
having an outer diameter sized to permit said cylindrical portion
to be received at the end thereof by the uppermost portion of said
tank body, said cylindrical portion having a flared peripheral
section at the other end thereof, said flared peripheral section
adapted to be positioned at the surface level of the area in which
the tank is located; and
a detector mounted on the upright wall of said body to detect the
level of the pool water in said tank, said detector providing a low
electrical connection whenever the pool water level is below an
established low water level, and said detector providing a high
electrical connection whenever the pool water level is above an
established high water water level.
2. The apparatus defined by claim 1, said detector including:
water level means for continually sensing the level of said pool
water in the tank body by being maintained at the level of said
pool water;
switching means for providing a high or a low electrical
connection; and
connector means coupled between said water level means and said
switching means for operating said switching means to produce a
high connection or a low connection in response to the water levels
above said established high water level or below said established
low water level, respectively.
3. The apparatus defined by claim 2, said water level means
including a buoyant member situated to assume a position
corresponding to the level of the pool water in said tank body, and
a supporting rod connected at one end to said buoyant member and
having a center portion adapted to permit adjustable attachment to
said connector means.
4. The apparatus defined by claim 1, further including a grate for
covering any surface opening provided by said deck flange.
5. The apparatus defined by claim 1, said aperture provided by a
cylindrical section integrally formed with said floor and having an
axial bore extending for the length thereof and through said floor,
said cylindrical section extending to receive an end of a conduit
for permitting water to flow between said pool and said tank.
6. The apparatus defined by claim 1 further comprising a grate
sized to be centrally positioned within said flared peripheral
section of said deck flange, said grate covering the central
aperture of the flared end of said cylindrical portion of said deck
flange.
7. The apparatus defined by claim 6, said detector including:
water level means for continually sensing the level of said pool
water in the tank body by being maintained at the level of said
pool water;
switching means for providing a high or a low electrical
connection; and
connector means coupled between said water level means and said
switching means for operating said switching means to produce a
high connection or a low connection in response to the water levels
above said established high water level or below said established
low water level, respectively.
8. The apparatus defined by claim 7, said water level means
including a buoyant member situated to assume a position
corresponding to the level of the pool water in said tank body, and
a supporting rod connected at one end to said buoyant member and
having a center portion adapted to permit adjustable attachment to
said connector means.
9. The apparatus defined by claim 8, said aperture provided by a
cylindrical section integrally formed with said floor and having an
axial bore extending for the length thereof and through said floor,
said cylindrical section extending to receive an end of a conduit
for permitting water to flow between said pool and said tank.
10. A water level control for swimming pools including the
combination of:
sensing means for continually monitoring the level of water in said
pool, said sensing means capable of being remotely located away
from said pool, said sensing means completing first and second
electrical connections in response to the water level being above
an established high level or below an established low level,
respectively, said sensing means including:
a secondary tank for containing pool water therein, said tank
including a closed wall and a floor, said conduit means being
connected to permit pool water to be supplied to said secondary
tank,
detector means positioned in said secondary tank to detect the
level of pool water therein,
flange means for extending the wall of said tank, said flange
having a flared peripheral portion suitable for being maintained
level with the surface of the area in which said secondary tank is
positioned, said flange permitting said tank to be open at said
surface, and
grate means for covering the tank at said surface, said grate means
adapted to be centrally received by said flange means, said grate
means having perforations therethrough for permitting said water in
said secondary tank to be exposed to the atmosphere;
conduit means for connecting said pool to said sensing means to
permit the flow of water therebetween such that said sensing means
is unaffected by waves on the surface of the water in said
pool;
draining means responsive to the completion of said first
electrical connection for effecting the removal of water from said
pool to have said water level adjusted to be no higher than said
established high level; and
filling means responsive to the completion of said second
electrical connection for permitting the addition of water to said
pool to have said water level adjusted to be no lower than said
established low level.
11. The apparatus defined by claim 10, said draining means
including a pump operatively connected to remove water from said
pool in response to the presence of said first electrical
connection, said water removal continuing until at least said
established high water level is attained.
12. The apparatus defined by claim 10, said filling means including
a solenoid operated valve for permitting the flow of water into
said pool in response to the presence of said second electrical
connection, said addition of water continuing until at least said
established low water level is attained.
13. The apparatus defined by claim 12, said detector means
including:
water level means for continually sensing the water level in said
secondary tank, said water level means adapted to follow variations
in the level of the water in said secondary tank;
switching means for completing said first and second electrical
connections; and
arm means coupled to said water level means and said switching
means for operating said switching means to produce said first
electrical connection in response to water being at a level higher
than said established high level and said second electrical
connection in response to water receding below said established low
level.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to devices for controlling the
level of water in a swimming pool. More specifically, the present
invention concerns apparatus for use in a control system to
maintain the water in a swimming pool at an established level.
2. Description of the Prior Art
The maintenance of a swimming pool requires that a generally
established range of water levels be maintained for the water in
the pool. Failure to maintain this established water level can
result in damage to circulation and filtration accessories and/or
the area surrounding a swimming pool.
Considering first the circulation accessories, a swimming pool is
typically equipped with a filtration system including a filter and
a motor/pump combination that serves to pump water from the pool
through the filter for return to the pool. The motor is normally
designed to operate under a load provided by a continuing head of
water in the pump. Should this load fail to be present while the
motor is operated, serious and/or permanent damage may in time
result. Clearly, such damage is costly and an inconvenience since
the motor must be promptly repaired and/or replaced to avoid the
growth of algae.
An abnormally low water level is one of the primary factors
contributing to the absence of the water load at the pump. In turn,
a decreased water level may be caused by the usual splashing by
swimmers or, more commonly, evaporation. During the summer months,
evaporation may require that water be added at least once a week.
With such a requirement, it is inadvisable to leave a pool
unattended for longer periods of time. Thus, vacationing pool
owners must obtain the services of someone to maintain the pool
while the owners are away, to avoid damage to the motor.
Damage to the area surrounding the swimming pool can result from
the swimming pool overflowing. This may occur as a result of heavy
rains. The damage usually results from the chemicals in the pool
water harming surrounding foliage.
A number of devices have been designed for use in controlling the
water level of a swimming pool. However, to the inventor's
knowledge these prior art devices have the disadvantage of being
affected by activity in the pool such that when the pool is in use,
the water sensing device must frequently be disabled to prevent its
false operation. Prior art devices also have the disadvantage of
including some mechanical linkage between a sensor and a refill
device. As a result, the flow of refill water is reduced to a
dribble as the established normal level is approached. Finally,
most prior art control systems are designed to add water to a pool,
while ignoring the problem of overflow water.
It is thus the intention of the present invention to provide a
water level maintenance device which operates to automatically
maintain the water level of a swimming pool at an estabilished
level or range of levels wherein water is automatically added to
the swimming pool to avoid undesirably low levels and excessive
water is automatically drained from the pool to avoid excessive
water levels and/or overflow.
SUMMARY OF THE INVENTION
Briefly described, the present invention involves a water-level
tank for sensing the water level in a swimming pool and correcting
for abnormally low or high levels by respectively adding water to
or draining water from the pool.
More particularly, the subject water level maintenance device
includes a water-level tank that is connected via a conduit to
receive water from the pool such that the level in both the pool
and the tank are at the same level. A float switch is mounted to
continually sense the water level in the tank and thus the water
level in the swimming pool. Upon the detection of abnormally low
levels, the float switch energizes an electrical solenoid valve
coupled in a refill water line and hence permits water to be added
to the swimming pool to correct for the water deficiency. Excessive
water levels detected by the float switch causes the energization
of a secondary pump which operates to drain water from the pool
until the estabilished water level is attained.
The objects and many attandant advantages of the invention will be
more readily appreciated as the same becomes better understood by
reference to the following detailed description which is to be
considered in connection with the accompanying drawings wherein
like reference symbols designate like parts throughout the figures
thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram illustrating a cross-sectional view
of a swimming pool accompanied by a typical filtration system and a
water level maintenance device connected in accordance with the
present invention.
FIG. 2 is a schematic diagram illustrating a cross-sectional view
of a water level maintenance device in accordance with the present
invention.
Referring to FIG. 1 of the drawings, a swimming pool 10 is
customarily provided with a main drain 12 situated at the bottom of
the deep end of the pool 10 and a skimmer 14 situated along a side
of the pool 10. Characteristically, both the main drain 12 and the
skimmer 14 operate to provide water to a filter 16 for return to
the pool 10. A pump 18 driven by a motor 20 serves to draw the
water through the conduits 22 and 24 connected respectively to the
main drain 12 and the skimmer 14. A valve 26 is usually provided to
adjust the distributed proportion of water flow from the main drain
12 and the skimmer 14.
As is well known, the filtration system accompanying a swimming
pool may be operated daily for five or more hours depending on the
season and usage. The filtration, and circulation, of the water in
the swimming pool is necessary to keep the water pure and the
swimming pool generally clean. Excessive amounts of refuse, such as
leaves and/or accumulated dust, generally must be removed with
auxiliary equipment such as a swimming pool vacuum.
The skimmer 14 serves to cause circulation of the surface water of
the swimming pool to prevent the accumulation of floating particles
that may contribute to a scum forming at the surface if not drawn
off by the skimmer 14. Accordingly, the normal practice is to have
both the main drain 12 and the skimmer 14 in operation
concurrently. The proportional flow of pool water through the main
drain 12 and skimmer 14 is adjusted with the valve 26 as desired by
a pool owner.
As earlier briefly mentioned, abnormally low water levels will
result in the load on the motor 20 being either significantly
decreased or eliminated all together. This will normally occur as a
result of the water level dropping to a point that permits air, and
hence less water, to be drawn through the skimmer 14. Of course,
where the water level drops below the level of the weir 28 of the
skimmer 14, no water at all will be drawn through the skimmer 14
and water will fail to be drawn by the pump 18. The motor 20
consequently will be operated under a no-load condition which will
quickly cause overheating and consequent damage thereto.
Accordingly, the water level maintenance device of the subject
invention operates to detect abnormally low water levels and
automatically cause water to be added to the pool to maintain the
water at an established normal level. To this end, a water level
tank 30 is buried in reasonable proximity to the pool 10 and
connected thereto via a conduit 32 such that the water level in the
pool 10 and the tank 30 will be the same.
Briefly, the conduit 32 is connected to the swimming pool 10 at the
deep end such that activity in the pool causing waves, or other
undulation of the water surface, will leave the water level in the
tank 30 unaffected. The water level in the tank 30 is thus calm
despite activity in the swimming pool and hence nned not be
disabled while a swimming pool is in use to prevent false
operation. The conduit 32 may be buried and of the necessary length
to permit the tank 30 to be installed in a remote location if
desired.
The water level in the pool 10 and tank 30 is sensed by a
double-pole float switch 34 which operates to energize a solenoid
valve 36 coupled in series with a water main 38 from which water
may be added to the pool 10. Any conventional electrically operated
solenoid valve that is readily available and well known in the
prior art may be used.
The subject water level maintenance device also operates to correct
for excessive water in the pool. This is accomplished by having the
float switch 34 also detect abnormally high water levels and cause
the operation of a secondary pump 40 which serves to pump water out
of the pool 10 and into a drain or sewer line as is convenient. The
pump 40 may be connected to the pool 10 by having a conduit 42
connected to the conduits 22 and 24, as shown. In the alternative,
the conduit 42 may be directly connected to the pool 10. The
secondary pump 40 may be any conventional centrifugal pump similar
to the pump 18 operated by a motor 44. The motor 44 may also be any
conventional motor available and of adequate horse power to
accomplish the stated purpose.
It is recognized that in some instances such as in the presence of
heavy rainfall, water may be added to the pool at a somewhat high
rate. Accordingly, the motor 44 and pump 40 should be adequate to
prevent overflow and hence distribution of the pool water about the
pool area.
The water level maintenance device may now be considered in greater
detail by reference to FIG. 2. As shown, the water level tank 30
includes a main body 46 which is provided with an oversized upper
portion 48. A deck flange 50 having an outer diameter sized to be
snuggly received within the oversized upper portion 48, is
positioned in telescoping relationship with the body 46 of the tank
30. A grate cover 52 is used to eliminate the aperture of the deck
flange 50. A peripheral shoulder portion 53 is provided to support
the grate cover 52. Numerous perforations 54 are provided in the
grate cover 52 to permit the atmosphere to readily act upon the
water 56 in the tank 30. The floor 55 of the tank 30 is provided
with a drain 58 which is shaped to receive the conduit 32 at a
mouth 60 thereof.
It is to be understood that the tank body 46 may have any
reasonable configuration suitable for the described purpose. As an
example, the tank body 46 may be cylindrical, etc.
The tank body 46 and deck flange 50 are preferably made of
non-corrosive material to prevent and/or resist chemical reaction
with either the chemicals in the swimming pool water and/or the
soil in which the tank 30 is embedded.
The oversizing of the upper portion 48, to permit the telescoping
adjustment of the flange 50, allows the tank body 46 to be readily
emplaced to have the water level within the pool 10 and the tank 30
the same and within the operating range of the double pole solenoid
switch 34. The flange 50 by being telescoping may then be readily,
later leveled with the decking surrounding a pool, and yet have the
tank 30 include a continuous wall between the deck, or ground
level, and the tank floor 55.
Considering the double pole switch 34 in greater detail, any
available double pole float switch, such as that marketed by Cutler
Hammer, Inc., would be suitable. Characteristically, the switch 34
includes a float 62 attached to the end of a supporting rod 64
which is maintained at a generally vertical position on a switch
arm 66. The rod 64 and hence the float 62 is adjustable on the arm
66 for the purpose of establishing a range of water levels. To this
end, the mid portion of the supporting rod 64 may be threaded to
accommodate a pair of lock nuts 68 and 70 which operate to secure
the rod 64 in a selected position with respect to the arm 66. The
end of the switch arm 66 may be notched or apertured to receive the
supporting rod 64.
As an example, the water level shown in FIG. 2 may represent a low
threshold below which the switch 34 is operated to energize the
solenoid valve 36 by further downward rotation of the arm 66 to
make a first electrical contact or connection. Excessive water in
the swimming pool 10, represented by an abnormally high water level
as illustrated by the dotted line 72, serves to raise the float
62.
The switch arm 66, as shown in dotted lines, is accordingly rotated
upward to make a second electrical contact and thereby energize the
motor 44 to cause the pump 40 to drain water from the pool 10. Upon
restoration of the pool water level to the established range of
levels, the first and second electrical contacts are broken and the
energized solenoid 36 or pump motor 44 are deactivated. The use of
the electrical switch 34 clearly presents the advantage of positive
opening and closure of the electrical solenoid 36 and pump motor
44. As earlier mentioned, the prior art mechanical linkages are
bulky and restrict the placement of the switch, valve, etc. with
respect to each other.
An electrical conduit 74 may be used to direct the necessary
electrical cable from the double pole float switch 34 to an
appropriate power line and to the motor 44 and the solenoid 36. A
lock nut 76 is adapted to communicate with the electric connection
78 of the switch 34 which extends through the wall of the tank
30.
In that the actual connection of the electric cables between the
switch 34, the solenoid 36, the motor 44, and a power source may be
accomplished in any well known manner, a detailed description
thereof has been omitted herefrom.
From the foregoing description, it is now clear that the subject
invention provides a water level maintenance device which is
unaffected by activity in the pool and which operates to
automatically maintain the water level of a swimming pool within an
established range of levels such that a load is always provided to
the pump 18 of the filtration system and overflowing of the
swimming pool is prevented.
While a preferred embodiment of the present invention has been
described hereinabove, it is intended that all matter contained in
the above description and shown in the accompanying drawings be
interpreted as illustrative and not in a limiting sense and that
all modifications, constructions and arrangements which fall within
the scope and spirit of the invention may be made.
* * * * *