Water pressure system

BACKGROUND OF THE INVENTION

The present invention relates to water pressure systems for water wells, and more particularly, to a pressure tank installed underground in the well casing of a well, and used in combination with a flow control valve or a variable speed pump in a water pressure system.

A typical water pressure system for a home is established by first drilling a hole in the ground in search of water from a water bearing aquifer. Once water is reached by the drill, a well casing is inserted into the bore hole to preserve the sides of the well. A submersible pump is then inserted into the well below the water level to pump water from the aquifer. One end of a drop pipe is attached to the submersible pump to draw water out of the well. The other end of the drop pipe is attached to a pitless adapter, which is attached to a discharge pipe for carrying water to a pressure tank located in the house or in another building next to the house. Water from the pressure tank is then distributed throughout the house for use.

The pressure tank holds a reserve supply of water under pressure within the tank. A pressure switch coupled to the tank is used to maintain water pressure in tank between a minimum value and a maximum value. The pressure switch activates the submersible pump to pump water into the tank when the water pressure in the tank drops below to the minimum value. Water is then pumped into the tank to replenish the tank with water and to build up the pressure in the tank to its maximum value. Once the pressure in the tank has reached its maximum value, the pressure switch stops the pump from operating. The switch activates the pump generally whenever water is drawn from the tank. The water is stored in the tank under pressure until it's needed. As water is drawn from the tank, the pressure in the tank decreases. Upon reaching the set minimum pressure, the pressure switch automatically activates the pump.

Pressure tanks are normally of substantial size, and consequently are limited to above ground installations in water pressure systems. Typically, pressure tanks are installed in the basement of a house or in a separate building near the house to protect it from the elements. This is especially true in cold climates. Adverse weather conditions can effect the reliability of a pressure tank in cold weather. During the winter months, the pressure tanks must be protected from the cold and snow. Therefore, the tanks are either installed in a basement or in an insulated building above ground.

However, there are problems associated with above ground installations of pressure tanks. A problem with installing a tank in the basement of a building is that the tank may take up valuable space in the home. Also, the installation of the pressure tank can be quite difficult and time-consuming. In addition, the installation of a pressure tank above ground in cold weather climates may require the tank be installed in a separate insulated building. And the tank must often be wrapped in insulation and heat tape.

Water pressure tanks installed underground are known in the art. For example U.S. Pat. No. 3,394,733 to Jacuzzi discloses an airless water pressure system utilizing an underground pressure tank. The pressure tank of this invention includes an expansible tube installed around a pipe having openings therein to transfer liquid from the pipe to the expansible tube. The tube is clamped at each end to allow the liquid under pressure to cause expansion of the tube. However, the clamped ends of the tube have been known to fail under pressure from the liquid. In another patent to Jacuzzi, U.S. Pat. No. 3,442,292 discloses a pressure tank installed underground in a well, having water flowing into the pressure tank around an air filled bladder. The problem with this patented invention is that the air filled bladder seals off water flow from the inlet end of the tank to the outlet end of the tank. In other words, water freely flows into the tank but is sealed off from exiting the tank by the air filled bladder pressing against the walls of the tank.

Accordingly, there is a need for a water pressure system that allows for installation of a pressure tank underground in the well casing of a water well, that is more reliable in cold weather, less expensive to install, and more easily maintained than prior art systems.

SUMMARY OF THE INVENTION

The present invention is a new arrangement for a well pressure tank used in water pressure systems utilizing water wells. In most existing home water pressure systems, the pressure tank is located either in the home or in a separate building near the home. The pressure tank of the present invention is designed to be located in the well casing of a water well. A typical well casing is approximately six inches in diameter. The tank of the present invention is approximately four inches in diameter and approximately ten feet long. The tank has a draw down capacity of approximately 1-3 gallons of water. The pressure tank of the present invention is reduced in size, more reliable in cold weather, less expensive to install, and more easily maintained than prior art pressure tanks.

The water pressure system of the present invention pumps water from a water bearing aquifer to a pressure tank installed underground in the well casing of a well. The water pressure system includes a submersible pump inserted in the well below the water level to pump water from the aquifer. One end of a first drop pipe is attached to the submersible pump, while the other end of the first drop pipe is attached to an inlet opening in a pressure tank installed in the well casing of the well. Water flows from the submersible pump through the drop pipe and into the pressure tank. The water enters the pressure tank through the inlet opening, and is either stored in the tank for future use, or continues to flow out through an outlet opening in the tank. One end of a second drop pipe is connected to the outlet opening in the tank. The other end of the second drop pipe is attached to a pitless adapter which is connected to a discharge pipe for carrying pressurized water to a house or other building for use.

The pressure tank includes a main body having an inlet end, an outlet end, and an outer sidewall. Attached to the inlet end of the tank are an inlet end cap and an inlet plug. The inlet plug is inserted within the inlet end cap. An expandable diaphragm bladder is connected between the inlet plug and the outlet end cap. A tube extends through the center of the expandable diaphragm bladder between an inlet opening and an outlet opening. The tube has a plurality of holes therein to allow water to flow through the tube and into and out of the expandable bladder. The inlet opening of the diaphragm bladder is clamped to a ribbed end of the inlet plug with a clamping device. The outlet opening of the diaphragm bladder is clamped to a ribbed end of the outlet end cap with a similar clamping device. Pressurized air fills the empty space between the bladder and the outer sidewall of the tank to pressurize the water in the expandable bladder.

The outlet end of the drop pipe opposite the end connected to the submersible pump is connected to the inlet plug extending through the inlet end cap of the pressure tank. The other end of the inlet plug is connected to the inlet end of the diaphragm bladder. The outlet end of the diaphragm bladder is attached to the outlet end cap. Water flows through the openings in the inlet end cap, inlet plug, diaphragm bladder, and outlet end cap to a second drop pipe connected to the outlet end cap of the tank. The other end of the second drop pipe is connected to a pitless adapter, which in turn is connected to a discharge pipe for carrying water to the home.

A pressure switch coupled to the pressure tank regulates water pressure in the pressure tank by maintaining the water pressure between a minimum value and a maximum value. The pressure switch continuously monitors the water pressure in the tank, and controls the submersible pump accordingly. The pressure switch responds to a drop in pressure below the minimum value by starting the pump to replenish the water in the tank and to build up the water pressure to its maximum value. The pressure switch stops the pump when the water pressure reaches the maximum value and restarts the pump when the pressure drops below the minimum value.

A first embodiment of the invention includes the well pressure tank used in combination with a flow control valve. The flow control valve automatically adjusts the submersible pump's output to match the flow requirements of the user. The flow control valve maintains constant water pressure in the system. The flow control valve eliminates changes in water pressure and reduces the need for a large storage pressure tank.

A second embodiment of the invention includes the well pressure tank used in combination with a variable speed pump. The variable speed pump performs much the same function as the flow control valve, so that the flow control valve is no longer needed in the water pressure system to maintain constant water pressure. In this embodiment, constant water pressure is maintained by continuously adjusting pump speed to meet water demand. This type of system also minimizes pressure cycling during long-running applications, such as when someone is taking a shower.

Various other features, objects, and advantages of the invention will be made apparent to those skilled in the art from the following drawings and detailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode presently contemplated of carrying out the invention.

In the drawings:

FIG. 1

is a partial cross-sectional side view of a well pressure tank constructed in accordance with the present invention;

FIG. 1

a

is an enlarged partial cross-sectional view of the inlet end of the well pressure tank of

FIG. 1

;

FIG. 1

b

is an enlarged exploded view of the components of the inlet end of the tank of

FIG. 1

a;

FIG. 1

c

is an enlarged partial cross-sectional view of the outlet end of the well pressure tank of

FIG. 1

;

FIG. 1

d

is an enlarged view of an outlet end cap of the tank of

FIG. 1

c;

FIG. 2

a

is a partial cross-sectional schematic view of a first embodiment of a well pressure tank used in combination with a flow control valve to maintain constant water pressure in the system;

FIG. 2

b

is a partial cross-sectional schematic view of the well pressure tank of

FIG. 2

a

filled with water;

FIG. 3

a

is a partial cross-sectional schematic view of a second embodiment of a well pressure tank used in combination with a variable speed pump; and

FIG. 3

b

is a partial cross-sectional schematic view of the well pressure tank of

FIG. 3

a

filled with water.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1

is a partial cross-sectional side view of a water pressure system

10

for a water well constructed in accordance with the present invention. The water pressure system

10

includes a submersible pump

11

installed in the well below the water level to pump water from a water bearing aquifer. A first end

19

of a first drop pipe

18

is attached to the submersible pump

11

, while a second end

20

of the first drop pipe

18

, opposite the first end

19

, is attached to an inlet end

14

of a pressure tank

12

installed in the well casing

22

of a well. The well casing

22

is approximately six inches in diameter, while the pressure tank

12

is approximately four inches in diameter and approximately ten feet long. Water flows from the submersible pump

11

through the first drop pipe

18

and into the inlet end

14

of the pressure tank

12

as shown by arrow

24

. The water enters the pressure tank

12

through the inlet end

14

, and is either stored in the tank

12

for future use, or continues to flow out through an outlet end

16

in the tank

12

.

A first end

28

of a second drop pipe

26

is connected to the outlet end

16

of the pressure tank

12

. A second end

30

of the second drop pipe

26

, opposite the first end

28

, is connected to a pitless adapter

32

which is connected to a discharge pipe

34

for carrying pressurized water to a house or other building for use.

The pressure tank

12

includes an outer sidewall

36

with an inlet end

14

and an outlet end

16

. Connected between the inlet end

14

and the outlet end

16

is an expandable diaphragm bladder

38

surrounded by pressurized air for storing a reserve supply of water in the tank

12

. A tube

40

extends through the center of the expandable diaphragm bladder

38

from the inlet end

14

to the outlet end

16

. The tube

40

includes a plurality of holes

42

extending therethrough to allow water to enter and exit the expandable bladder

38

. Water is pumped up through the first drop pipe

18

from the submersible pump

11

and into the inlet end

14

of the pressure tank

12

where it is stored for future use in the expandable diaphragm bladder

38

. The water is then pumped out of the bladder

38

through the outlet end

16

of the tank

12

and into a second drop pipe

26

to a pitless adapter

32

, where it is transferred to a discharge pipe

34

for distribution and use.

FIGS. 1

a

and

1

b

illustrate the inlet end

14

of the tank

12

.

FIG. 1

a

is an enlarged partial cross-sectional view of the inlet end

14

of the well pressure tank

12

, while

FIG. 1

b

is an enlarged exploded view of the components that connect the inlet end

14

of the tank

12

to the first drop pipe

18

. The inlet end

14

of the tank

12

includes an inlet end cap

44

and an inlet plug

46

extending through the inlet end cap

44

. The inlet end cap

44

includes a bottom flange

48

and a cylindrical top portion

50

with standard pipe threads formed therein for attachment to a bottom portion

52

of the sidewall

36

having mating pipe threads formed on the inner surface of the sidewall

36

. The inlet end cap

44

is preferably screwed into the inlet end

14

of the tank

12

. An o-ring

54

located on an inner portion of the flange

48

seals the end cap

44

to the sidewalls

36

and inlet end

14

of the tank

12

.

Inserted within the inlet end cap

44

is an inlet plug

46

, having a first end

56

for attachment to the first drop pipe

18

and a second end

58

for attachment to an inlet end

62

of the expandable bladder

38

within the tank

12

. The first end

56

having threads for attachment of a fastener

60

to secure the inlet plug

46

in place within the inlet end cap

44

. The second end

58

of the plug

46

includes a plurality of ribs

68

for connecting the inlet end

62

of the bladder

38

to the plug

46

. A clamping device

70

fits over the ribs

68

of the second end

58

of the plug

46

to secure the inlet end

62

of the bladder

38

to the plug

46

. An o-ring

64

located around a center portion of the plug

46

seals the connection between the plug

46

and the end cap

44

. An opening

66

extending through the inlet plug

46

allows water to flow through the plug

46

to the tube

40

within the bladder

38

.

FIGS. 1

c

and

1

d

illustrate the outlet end

16

of the tank

12

.

FIG. 1

c

is an enlarged partial cross-sectional view of the outlet end

16

of the tank

12

, while

FIG. 1

d

is an enlarged view of an outlet end cap

72

that connects the outlet end

16

of the tank

12

to the second drop pipe

26

. The outlet end cap

72

includes a top flange

74

for enclosing the outlet end

16

of the tank

12

, a center portion

76

for securing the outlet end cap

72

to the outer sidewall

36

, and a bottom portion

78

for connecting the outlet end cap

72

to an outlet end

84

of the bladder

38

. The center portion

76

having threads embedded therein for mating with threads on the inner surface of a top portion

82

of the outer sidewall

36

. The bottom portion

78

having ribs

80

for securing the outlet end

84

of the bladder

38

to the outlet end cap

72

. A clamping device

92

fits over the ribs

80

of the bottom portion

78

to secure the outlet end

84

of the bladder

38

to the outlet end cap

72

.

The top flange

74

has connections

86

,

88

for connecting the outlet end

16

of the tank

12

to the second drop pipe

26

and a pressure switch

98

. The bottom portion

78

of the outlet end cap

72

has a connection

90

for connecting to the tube

40

within the bladder

38

. A first opening

94

extending through the outlet end cap

72

between the tube connection

90

and the second drop pipe connection

86

allows water to flow from the tube

40

within the bladder

38

through the outlet end cap

72

to the second drop pipe

26

. A second opening

96

extending through the flange

74

and the center portion

76

of the outlet end cap

72

allows pressurized air to flow from the pressure tank

12

to the pressure switch

98

. An o-ring

100

located on an inner portion of the top flange

74

seals the outlet end cap

72

to the sidewall

36

of the outlet end

16

of the tank

12

.

Referring again to

FIG. 1

, the expandable diaphragm bladder

38

is connected between the inlet plug

46

and the outlet end cap

72

. The inlet end

62

of the bladder

38

is clamped to ribs

68

on the second end

58

of the inlet plug

46

with a clamping device

70

. The outlet end

84

of the bladder

38

is clamped to ribs

80

on the bottom portion

78

of the outlet end cap

72

with a similar clamping device

92

. The tube

40

extends through the center of the expandable diaphragm bladder

38

between the inlet end

62

and the outlet

84

. The tube

40

has a plurality of holes

42

therein to allow water to flow into and out of the expandable bladder

38

. Pressurized air fills the empty space between the bladder

38

and the outer sidewall

36

of the tank

12

to pressurize the water. The components of the pressure tank

12

are preferably made out of a non-corrosive sanitary material, such as plastic or PVC to eliminate corrosion and bacterial growth. The expandable diaphragm bladder

38

is preferably made out of butyl rubber.

FIGS. 2

a

and

2

b

illustrate the operation of a first embodiment of the present invention.

FIG. 2

a

shows a pressure tank

12

installed in the well casing

22

of a well. The pressure tank

12

is used in combination with a pressure switch

98

and a flow control valve

102

. One end of a first drop pipe

18

is connected to a submersible pump

11

, while the other end is connected to a flow control valve

102

. The flow control valve

102

is connected to the inlet end

14

of the pressure tank

12

. The pressure tank is comprised of an inlet end

14

, an outlet end

16

, and an outer sidewall

36

. Within the outer sidewall

36

of the tank

12

is an expandable diaphragm bladder

38

surrounded by an open area pre-charged with pressurized air

106

. The open area

106

in the tank surrounding the bladder

38

is pre-charged with air to a pre-set amount depending on the desired operating pressure. A pressure switch

98

is coupled to the tank

12

with an air line

104

to monitor the pressure within the tank

12

and to control operation of the pump

11

accordingly. There is an air line

104

running from the pressure switch

98

to the tank

12

. The flow control valve

102

maintains the flow of water through the system at a constant pressure. Openings

42

in a center tube

40

within the bladder

38

allow water to flow into and out of the bladder as pressure in the tank

12

varies. As water demand increases, pressure in the tank decreases.

The pressure switch

98

coupled to the pressure tank

12

regulates water pressure in the tank

12

by maintaining the water pressure between a minimum value and a maximum value. The pressure switch

98

continuously monitors the pressure in the tank

12

, and controls the submersible pump

11

accordingly. The pressure switch

98

responds to a drop in pressure below the minimum value by starting the pump

11

to replenish the water in the tank

12

and to build up the water pressure to its maximum value. The pressure switch

98

stops the pump

11

when the water pressure reaches the maximum value and restarts the pump

11

when the pressure drops below the minimum value.

FIG. 2

a

shows the tank

12

with little or no water in the expandable diaphragm bladder

38

.

FIG. 2

b

shows the expandable bladder

38

of

FIG. 2

a

virtually filled with water.

FIGS. 3

a

and

3

b

illustrate the operation of another embodiment of the present invention.

FIG. 3

a

is a schematic view of a second embodiment of a water pressure system with a pressure tank

12

installed in the well casing

22

of a well, and utilizing a variable speed pump

11

to maintain constant water pressure in the system. This embodiment does not include the use of a flow control valve. Constant water pressure is maintained by continuously adjusting pump speed to meet water demand. A pressure switch

98

coupled to the pressure tank

12

controls the speed of the variable speed pump

11

. This type of system also minimizes pressure cycling during long-running applications. Water enters the pressure tank

12

through an inlet end

14

, and is either stored in the tank

12

for future use, or continues to flow through the tank

12

and out its outlet end

16

. The water flows through a tube

40

in the tank

12

and into the expandable bladder

38

which is surrounded by pressurized air in the tank. The water filled bladder

38

stretches or contracts as the water pressure varies. The pressure switch

98

monitors the pressure in the tank and adjusts the speed of the pump

11

accordingly.

FIG. 3

a

shows the bladder

38

with little or no water inside it, while

FIG. 3

b

shows the bladder

38

virtually filled with water.

While the invention has been described with reference to preferred embodiments, those skilled in the art will appreciate that certain substitutions, alterations and omissions may be made without departing from the spirit of the invention. Accordingly, the foregoing description is meant to be exemplary only, and should not limit the scope of the invention set forth in the following claims.