Information
-
Patent Grant
-
6698714
-
Patent Number
6,698,714
-
Date Filed
Tuesday, July 17, 200124 years ago
-
Date Issued
Tuesday, March 2, 200421 years ago
-
Inventors
-
-
Examiners
- Look; Edward K.
- Fristoe, Jr.; John K
Agents
-
CPC
-
US Classifications
Field of Search
US
- 285 1
- 285 2
- 285 215
- 285 216
- 285 219
- 285 341
- 285 13711
- 285 1372
- 285 356
- 285 357
- 251 148
- 251 150
- 251 151
- 222 396
- 137 6823
- 137 71
- 122 504
- 122 5041
-
International Classifications
-
Abstract
A fluid safety discharge system for a relief valve having an inlet and an outlet includes a bushing frictionally engaging the relief valve outlet. The relief valve outlet is internally threaded for engaging with a threaded device, such as a discharge line. The bushing may contain a separate body and engagement region for use with hard-plumbed discharge lines. Optionally, an adapter may be used for retrofitting the bushing to an existing relief valve.
Description
TECHNICAL FIELD
The present invention relates to the safe discharge of fluids and more particularly, to a pressure relief valve having a tamperproof outlet.
BACKGROUND INFORMATION
Common residential and commercial water heaters and boilers generally include a pressurized tank or vessel in which the heated water is stored until required for use. The temperature and pressure of the water stored within the tank will typically vary within predetermined limits when the water heater operates normally. However, when a malfunction occurs, the temperature and/or pressure of the water stored within even a common residential water heater are capable of inflicting severe damage. If the tank itself should fail, for example, due to excessive pressure in the water supply, boiling of the water, or age, high temperature water may be spread explosively from the tank over a considerable distance.
To avoid these catastrophic results, common residential and commercial water heaters and boilers always include a relief valve that releases water/steam when temperature and/or pressure of the water within the tank exceeds a predetermined value. The discharge side of the relief valve is generally threaded, allowing for the connection of a discharge pipe that releases the heated water into a reservoir or along the floor where there is less danger of injury to individuals.
While known relief valves are a significant and well-known safety feature of common water heaters and boilers, they often develop slow leaks. Many systems, however, do not utilize reservoirs or drains. As a result, homeowners often permanently plug the outlet of the relief valve to avoid the water from dripping onto the floor. The act of permanently plugging the relief valve is commonplace and has resulted in many injuries and deaths. This is due to the inability of the plugged relief valve to perform as it was intended.
Furthermore when left exposed, the outlet on the relief valve may become blocked by freezing, rust, improper sizing, and foreign materials such as dirt, leaves, etc. The situations described are also applicable to other relief valves such as those found on any pressurize (CO
2
, NO
2
, O
2
, etc.) tanks, boilers, or water/steam vessels.
For the above reasons, it would be desirable to provide a fluid discharge system that would allow reduce the possibility of blockage of the relief valve, while still allowing the relief valve to properly function when the condition in the tank or boiler becomes unsafe. Ideally, such a system should be low in cost and easily installable.
SUMMARY
The present invention is a fluid safety discharge system. The system comprises a relief valve and a bushing. The bushing has a body and internal threads. The bushing engages frictionally with a discharge outlet of the relief valve and allows the bushing to disengage from the relief valve at a predetermined pressure, thereby allowing the relief valve to perform as intended even if the bushing or connected piping is plugged. The system may optionally be coupled to a discharge line.
The bushing may optionally include an adapter portion for use with an existing relief valve. Additionally, the bushing may include a tamper-proof device that further prevents a homeowner from removing it from the relief valve.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein:
FIG. 1
is a perspective view of one embodiment of the fluid safety discharge system of the present invention;
FIG. 2
is a side view of one embodiment of a bushing of the present invention;
FIG. 3
is an end view of one embodiment of the present invention;
FIG. 4A
is a side view of one embodiment of the body of a bushing;
FIG. 4B
is an end view of another embodiment of the body of a bushing;
FIG. 5
is a cross sectional view of one embodiment of the present invention;
FIG. 6
is a side view of another embodiment of the present invention;
FIG. 7
is an exploded view of one embodiment of the present invention with an existing relief valve;
FIG. 8
is another embodiment of the present invention;
FIG. 9
is a plan view of one embodiment of a bushing engagement portion of the present invention having a smooth outer surface;
FIG. 10
is a plan view of one embodiment of a bushing engagement portion of the present invention having a multi-sided outer surface;
FIG. 11
is an exploded view of one embodiment of the present invention including a tamper-proof device;
FIG. 12
is a perspective view of one embodiment of the present invention assembled having a discharge line;
FIG. 13
is an exploded view of another embodiment of the present invention including a bushing engagement portion having one or more notches; and
FIG. 14
is a plane view of a fluid safety discharge system in accordance with the present invention installed, as disclosed in one embodiment, on a hot water tank.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The fluid safety discharge system
10
,
FIG. 1
, according to the present invention comprises a relief valve body
11
and an internally threaded bushing
20
. The relief valve
11
may be any type of relief valve
11
designed for any type of fluid (i.e. liquid or gaseous). The relief valve
11
, as is well known in the art, has an inlet
12
, an outlet
14
, and a control mechanism represented generally at
13
. The inlet
12
is connected to the potentially hazardous source, e.g. a hot water heater (not shown). In one embodiment, the outlet
14
has walls
15
that are generally smooth.
The bushing
20
,
FIG. 2
, has a body portion
22
and a flange portion
23
which also includes a gripping region
21
,
FIG. 3
, such as a several sided flange which can be gripped by a pipe wrench. In a preferred embodiment, the body
22
is slightly tapered. The body
22
is sized so that when the bushing
20
releases from the outlet
14
, the remaining area for the hazardous material (e.g. hot water or steam) to exit is equal to, or greater than, the area that is required by state or local regulation.
The surface of the body
22
may be smooth,
FIG. 2
, or have undulating or alternating high and low protrusions
24
,
FIGS. 4A and 4B
. In one embodiment, the protrusions
24
′,
FIG. 4A
, are annular. In another embodiment, the protrusions
24
″,
FIG. 4B
, are longitudinal.
The protrusions
24
are designed to facilitate a frictional fit with the walls
15
of outlet
14
of the relief valve
11
. It should be noted that the bushing
20
need not create a watertight seal. In cold climates, for example, a water tight seal may allow the liquid to back up in the relief valve
11
outlet
14
and eventually freeze, thus blocking the relief valve
11
. Therefore, a non-water tight seal may be preferable.
The bushing
20
is typically made of a material having sufficient rigidity to allow the bushing to be secured to the outlet
14
of the relief valve
11
, yet flexible enough allow the bushing
20
to disengage the outlet
14
when sufficient pressure has built up. In a preferred embodiment, the material is a synthetic material, such as plastic, but may also be a metal or composite. The rigidity and flexibility of the material will depend upon the application, but is within the knowledge of one of ordinary skill in the art.
Additionally, the body
22
includes internal threads
25
,
FIG. 5
, typically IPS pipe threads, for engaging with a discharge pipe or other similar attachment fittings.
In a preferred embodiment, the bushing
20
,
FIG. 6
, is a two-part device that includes a body portion
22
and separate engagement portion
30
. This embodiment is particularly useful when the bushing
20
is coupled to a drain line
32
that is hard plumbed and will not easily disengage from the relief valve
11
such as when discharge pipe
32
passes through or is attached or bracketed to a wall or the like. The drain line
32
would be threaded into the engagement portion
30
.
In the event that the drain line
32
becomes plugged, the body portion
22
will release from the outlet
14
and the engagement portion
30
, thus allowing the relief valve
11
to function properly. Without a separate body portion
22
and engagement portion
30
, a hard plumbed drain line
32
could prevent the bushing
20
from disengaging. In this embodiment, the cross-sectional area
33
formed by one end of body portion
22
would be sized to provide enough area to meet applicable state or local codes.
In yet another embodiment, a retrofit system
40
,
FIG. 7
, may include a bushing
20
, which may be any one of the above-described embodiments, and a bushing adapter
42
. The adapter
42
is adapted to be threaded within an existing relief valve
44
and has an engagement region
46
, typically IPS threads, that engages the outlet threads
48
of the relief valve
44
. The adapter
42
also includes a bushing engagement region
50
that receives a bushing
20
and is sized to ensure that the system
40
complies with local regulations.
In a further embodiment of a retrofit system
52
,
FIG. 8
, there is provided a bushing
20
, which may be any one of the above-described embodiments, a bushing engagement portion
54
, and an adapter portion
56
. The adapter portion
56
is sized to fit within an existing relief valve
44
and includes an engagement region
46
, typically IPS threads, that engages the outlet threads
48
of the relief valve
44
.
The bushing engagement portion
54
is sized to ensure that the system
40
complies with local regulations and is held in place by the adapter portion
56
. The bushing engagement portion
54
can have a smooth outer surface
60
,
FIG. 9
, to further prevent homeowners from tampering with the system
52
or a multi-sided surface
62
, FIG.
10
.
In a preferred embodiment, the system
52
further includes a tamper-proof element
64
,
FIG. 11
, including, for example, but not limited to, a crush ring/pin or a locking ring, to prevent homeowners from removing the bushing engagement portion
54
to plug the relief valve
44
.
In yet another embodiment, the system
52
,
FIG. 12
may further include an adapter portion
56
having one or more tabs
57
, and a bushing engagement portion
54
,
FIG. 13
, having one or more notches
58
. During installation, the installer rotates the bushing engagement portion
54
wherein the tabs
57
on the adapter portion
56
engage the notches
58
on the bushing engagement portion
54
, thereby allowing the bushing adapter
56
to be screwed into the existing relief valve
44
.
In one embodiment, the tabs
57
are designed to bend or break at a predetermined torque, preventing the bushing from being removed from the valve. This allows the installer to torque the adapter portion
56
to the proper specification while at the same time preventing someone from removing the system
52
. In another embodiment, the tabs
57
engage the notches
58
in a ratchet motion wherein the adapter portion
56
can only be rotated in one direction. Alternatively, the tabs
57
and the notches
58
may be located on the bushing engagement portion
54
and the adapter portion
56
respectively without departing from the present invention.
When an unsafe condition exists in the tank or other attached device
36
,
FIG. 14
, the relief valve
11
opens thus mitigating the condition. When the pressure on the outlet
14
of the relief valve
11
reaches a predetermined point, the bushing
20
disengages the outlet
14
of the relief valve
11
thereby allowing the fluid to escape. Bushing
20
will prevent the unsafe blocking of the relief valve outlet by insuring that even if the outlet is plugged or blocked, the bushing
20
will be pushed out of the valve outlet.
Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention, which is not to be limited except by the following claims.
Claims
- 1. A fluid safety discharge system comprising:a relief valve comprising: an inlet; and an outlet having a dimension; and a bushing comprising: a body having an external dimension sized to frictionally engage said outlet of said relief valve and having an internally threaded region for engaging with a threaded device, wherein said bushing is adapted to disengage from said relief valve at a predetermined pressure allowing said relief valve to function as intended.
- 2. The fluid safety discharge system as claimed in claim 1 wherein said threaded device is a pipe thread bearing device.
- 3. The fluid safety discharge system as claimed in 1 wherein said body is a material selected from the group consisting of synthetics, metal, and composite.
- 4. The fluid safety discharge system as claimed in claim 1 wherein said bushing further comprises a gripping region on one end of said bushing.
- 5. The fluid safety discharge system as claimed in claim 1 wherein said bushing is tapered.
- 6. The fluid safety discharge system as claimed in claim 1 wherein said bushing further includes annular high and low regions on an exterior surface of said bushing.
- 7. The fluid safety discharge system as claimed in claim 1 wherein said bushing further includes longitudinal high and low regions on an exterior surface of said bushing.
- 8. The fluid safety discharge system as claimed in claim 1 further comprising a discharge tube attached to said bushing.
- 9. A fluid safety discharge system comprising:a relief valve comprising: an inlet; and an outlet having a dimension; and a two-piece bushing comprising: an engagement portion having an internally threaded region for engaging with a threaded device; and a body portion having an external dimension sized to frictionally engage said relief valve outlet and an internal dimension sized to frictionally engage said engagement portion, wherein said body portion is adapted to disengage from said relief valve outlet and from said engagement portion at a predetermined pressure allowing said relief valve to function as intended.
- 10. The fluid safety discharge system as claimed in claim 9 wherein said body portion includes a gripping region.
- 11. The fluid safety discharge system as claimed in claim 9 wherein said body portion is tapered.
- 12. The fluid safety discharge system as claimed in claim 9 wherein said body portion further includes annular high and low regions on an exterior surface of said body portion.
- 13. The fluid safety discharge system as claimed in claim 9 wherein said body portion further includes longitudinal high and low regions on an exterior surface of said body portion.
- 14. The fluid safety discharge system as claimed in claim 9 wherein said engagement portion is tapered.
- 15. The fluid safety discharge system as claimed in claim 9 further comprising a discharge tube attached to said bushing.
- 16. A system for connecting a fluid safety discharge system to an existing relief valve having an inlet and an outlet having an internally threaded region, said system comprising:an adapter comprising: a relief valve engagement region for threadably engaging said internally threaded region of said relief valve; and a bushing engagement region; and a bushing comprising: a body having an external dimension sized to frictionally engage said bushing engagement region of said adapter and a threaded section having an internally threaded region for engaging a threaded device, wherein said bushing is adapted to disengage from said bushing engagement region of said adapter at a predetermined pressure allowing said relief valve to function as intended.
- 17. The system as claimed in claim 16 wherein said relief valve engagement region and said bushing engagement region are separate.
- 18. The system as claimed in claim 16 further comprising a tamper-proof device for preventing a user from disabling said system, said tamper-proof device positioned between said bushing engagement region and said relief valve engagement region.
- 19. The system as claimed in claim 18 wherein said tamper-proof device is a locking ring.
- 20. The system as claimed in claim 18 wherein said relief valve engagement region further includes at least one tab and said bushing engagement region further includes at least one notch.
- 21. A system for connecting a fluid safety discharge system to an existing relief valve having a an inlet and an outlet having an internally threaded region, said system comprising:an adapter comprising: a relief valve engagement region for threadably engaging said internally threaded region of said relief valve; and a separate bushing engagement region; and a bushing comprising: a body having an external dimension sized to frictionally engage said bushing engagement region of said adapter and a threaded section having an internally threaded region for engaging a threaded device, wherein said bushing is adapted to disengage from said relief valve outlet at a predetermined pressure allowing said relief valve to function as intended.
- 22. The system as claimed in claim 21 further comprising a tamper-proof device for preventing a user from disabling said system, said tamper-proof device positioned between said bushing engagement region and said relief valve engagement region.
- 23. The system as claimed in claim 22 wherein said relief valve engagement region further includes at least one tab and said bushing engagement region further includes at least one notch.
- 24. The system as claimed in claim 22 wherein said tamper-proof device is a locking ring.
US Referenced Citations (5)