FIELD OF INVENTION:
[001] The present subject matter described herein, relates to the technical field of
water heaters. The present subject matter, in particularly, relates to a water heating
appliance with a long life.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART:
[002] Background description includes information that may be useful in
understanding the present invention. It is not an admission that any of the
information provided herein is prior art or relevant to the presently claimed
invention, or that any publication specifically or implicitly referenced is prior art.
[003] In today's world, the water heater has become one of the essential
household appliances. The job of the water heater is not only to heat the water, but
to store it until it's ready to use. Therefore, in addition to the tank's heating system,
every tank is equipped with insulation to help keep the water warm between heating
cycles.
[004] On top of every tank you'll find the water inlet and outlet pipes. The inlet
pipe routes cold water to the bottom of the tank through the dip tube. The hot-water
outlet pipe takes water from the top. For safety, all water heaters are equipped with
a multi-functional valve. This valve opens if either the temperature or pressure of
the water exceeds a safe limit. The valve is connected to a pipe that runs down the
outside of the tank, ending about 6 in. from the floor.
[005] The typical electric unit is wired to a 220-volt circuit. To heat the water, the
current passes through electrical-resistance heating elements—usually two, one at
the middle of the tank and one at the bottom. Power is delivered to each element
through a thermostat—a switch that senses the water temperature. When the
temperature drops, the switch closes to allow current flow, and it opens when the
temperature reaches its preset limit. Thermostats have a dial for setting the
maximum water temperature generally between 130 degrees and 140 degrees F, or
as low as about 120 degrees F for increased energy savings and scald protection.
[006] When a hot-water tap is opened, cold water enters the tank through the dip
tube and the drop in temperature triggers the thermostat and element at the bottom.
As the water at the top of the tank is replaced by cool water, the temperature at the
top thermostat drops and its element kicks in. When the tap is turned off, the heating
elements continue to carry current until the thermostats are satisfied.
[007] Typically, the decrease in the efficiency of the water heater is caused by
using hard water as well as silicates, sulfates, and similar materials which forms
water scale that coats the bottom of a hot water tank or a surface of electrodes in
the water heater. Because of this the existing water heater provides the poor thermal
conductivity of the scale, and when a large amount of scale is deposited on the
electrodes, this affects the heating efficiency. At the same time, the power
consumption increases. The presence of scale leads to overheating/low heating/no
heating of water as thermostat or thermal cutout may senses wrong temperature
which reduces the life of the water heater, and even endanger the personal safety of
users. The buildup of hard-water scale in water heaters leads to reduced heat
efficiency and may also shorten the heat service life.
[008] Currently, the water heaters use two separate sensor tubes for a thermostat
sensor and a thermal cut-out sensor. Apart from the scale formation on the heating
element and the heating zone around the heating element, the scale also gets formed
on the 2 sensor tubes. This results in incorrect reading by the thermostat sensor and
the thermal cut-out sensor. The incorrect readings further lead to the overheating or
no/less heating of the heating element.
[009] In case where the heating elements gets overheated, the life of the heating
element reduces substantially and in the case when the heating element is no heating
or there is less heating, the user remains dissatisfied.
[0010] Generally, the traditional practice is to directly place the thermostat sensor
and the thermal cut out sensor in the heating zone of the heating elements which
calls for their reliability issues.
[0011] Hence there is a need of such an arrangement wherein the overall cost of the
heating appliance is less than the conventional heating appliances and that such
heating appliance has an improved life span.
[0012] The information disclosed in this background of the disclosure section is
only for enhancement of understanding of the general background of the invention
and should not be taken as an acknowledgement or any form of suggestion that this
information forms the prior art already known to a person skilled in the art.
OBJECTS OF THE INVENTION:
[0013] It is therefore the object of the present subject matter to overcome the
aforementioned and other drawbacks in prior method/product/apparatus.
[0014] The principal objective of the present subject matter is to provide a single
enclosure for a thermostat and a thermal cutout.
[0015] Another object of the present subject matter is to eliminate scaling at the
heating zone, especially at a heating element and a sensor tube.
[0016] Another object of the present subject matter is to coat the sensor tube with
a coating material.
[0017] Another object of the present subject matter is to achieve constant
temperature sensing irrespective of the time of usage of the water heating appliance.
[0018] Another object of the present subject matter is to shift the zone of scale
deposition.
[0019] Yet another object of the present subject matter is to improve the reliability
of the water heating appliance.
[0020] Yet another object of the present subject matter is to improve the durability
of the water heating appliance in hard water environment.
[0021] Yet another object of the present invention is to reduce complexity and save
cost involved in the manufacturing of the water heating appliance.
[0022] These and other objects and advantages of the present subject matter will be
apparent to a person skilled in the art after consideration of the following detailed
description taken into consideration with accompanying drawings in which
preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION:
[0023] Solution to one or more drawbacks of existing positioning of thermostat
sensor and thermal cut-out sensor as disclosed in the present disclosure. Additional
features and advantages are realized through the technicalities of the present
disclosure. Other embodiments and aspects of the disclosure are described in detail
herein and are considered to be a part of the claimed disclosure.
[0024] According to one of the embodiment, the present subject matter relates to a
water heating appliance. The water heating appliance comprises a heating element,
a sensor tube and a combined thermostat and thermal cut out device. The sensor
tube is mounted upright proximal to the heating element. The combined thermostat
and thermal cut out device includes a thermostat and a thermal cut-out joined
together through fastening means. The combined thermostat and thermal cut-out
device comprises of a thermostat sensing bulb, a thermal cut-out sensing bulb, an
insulation wire for thermostat sensing bulb, an another insulation wire for thermal
cut-out sensing bulb and a spacer. The insulation wire integrally formed and
extending from the thermostat sensing bulb is coupled to the thermostat of the
combined thermostat and thermal cut out device. The other insulation wire
integrally formed and extending from the thermal cut-out sensing bulb is coupled
to the thermal cut-out of the combined thermostat and thermal cut out device. The
spacer is bombed over the insulation wires placed against each other through hot
air to adapt to their surface at a predetermined location in such a way that one end
of the insulation wire exists out of the spacer and the thermal cut-out sensing bulb
rests over the spacer. The thermostat and thermal cut-out sensing bulbs along with
the spacer are adapted to insert into the sensor tube in such a way that one sensing
bulb extends to the distal end of the sensor tube touching its one side surface and
the other sensing bulb lies below the sensing bulb touching the other side surface
of the sensor tube.
[0025] The foregoing summary is illustrative only and is not intended to be in any
way limiting. In addition to the illustrative aspects, embodiments, and features
described above, further aspects, embodiments, and features will become apparent
by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] It is to be noted, however, that the appended drawings illustrate only typical
embodiments of the present subject matter and are therefore not to be considered
for limiting of its scope, for the invention may admit to other equally effective
embodiments. The detailed description is described with reference to the
accompanying figures. In the figures, a reference number identifies the figure in
which the reference number first appears. The same numbers are used throughout
the figures to reference like features and components. Some embodiments of system
or methods or structure in accordance with embodiments of the present subject
matter are now described, by way of example, and with reference to the
accompanying figures, in which:
[0027] Fig. 1 illustrates a cut-sectional view of a water heating appliance according
to one of the embodiment of present subject matter;
[0028] Fig. 2 illustrates an enlarged view of a heating zone of figure 1 indicated by
a letter H, according to one of the embodiment of present subject matter;
[0029] Fig. 3 illustrates an enlarged view of a combined thermostat and thermal cut
out device of figure 1, according to one of the embodiment of the present subject
matter;
[0030] Fig. 4 illustrates a cut sectional view of a sensor tube of figure 2 according
to one of the embodiment of the present subject matter.
[0031] Fig. 5 illustrates a detailed arrangement of sensing bulbs of a thermostat and
a thermal cut out sensor according to one of the embodiment of present subject
matter.
[0032] The figures depict embodiments of the present subject matter for the
purposes of illustration only. A person skilled in the art will easily recognize from
the following description that alternative embodiments of the structures and
methods illustrated herein may be employed without departing from the principles
of the disclosure described herein.
DESCRIPTION OF THE PREFERRED EMBODIMENTS:
[0033] While the embodiments of the disclosure are subject to various
modifications and alternative forms, specific embodiment thereof have been shown
by way of example in the figures and will be described below. It should be
understood, however, that it is not intended to limit the disclosure to the particular
forms disclosed, but on the contrary, the disclosure is to cover all modifications,
equivalents, and alternative falling within the scope of the disclosure.
[0034] The terms "comprises", "comprising", or any other variations thereof used
in the disclosure, are intended to cover a non-exclusive inclusion, such that a device,
system, assembly that comprises a list of components does not include only those
components but may include other components not expressly listed or inherent to
such system, or assembly, or device. In other words, one or more elements in a
system or device proceeded by "comprises... a" does not, without more constraints,
preclude the existence of other elements or additional elements in the system or
device.
[0035] Referring to figure 1 & 2, there is provided a water heating appliance 100
comprising a heating element 102, a sensor tube 104 and a combined thermostat
and thermal cut-out device 110. The sensor tube 104 is mounted upright proximal
to the heating element 102 as shown in the figure 2. The combined area of the
heating element 102 and the sensor tube 104 is called as a heating zone and is
indicated by a letter 'FT. The combined thermostat and thermal cut-out device 110
is placed at the bottom of the water heating appliance 100 as shown in the figure 1.
The heating element 102 and the sensor tube 104 are made of stainless steel grade
SS 316 and coated with scale resistant material. The thickness of the scale resistant
material on the sensor tube 104 is 119 microns to 197 microns.
[0036] Referring to figure 3, 4 & 5, the combined thermostat and thermal cut-out
device 110 includes a thermostat 106 and a thermal cut-out 108 fastened together
through fastening means. The combined thermostat and thermal cut-out device 110
comprises a thermostat sensing bulb 106(a), a thermal cut-out sensing bulb 108(a),
an insulation wire 106(b) for thermostat sensing bulb 106(a), an another insulation
wire 108(b) for thermal cut-out sensing bulb 108(a) and a spacer 109.
[0037] The insulation wire 106(b) is integrally formed and extends from the
thermostat sensing bulb 106(a). The insulation wire 108(b) is integrally formed and
extends from the thermal cut-out sensing bulb 108(a).
[0038] The spacer 109 is bombed over the insulation wires (106(b) and 108(b)),
placed against each other, through hot air to adapt to their surface at a predetermined
location in such a way that one end 106(bl) of the insulation wire 106(b) exists out
of the spacer 109 and the thermal cut-out sensing bulb 108(a) rests over the spacer
109. The insulation wire 106(b) is coupled to the thermostat 106 of the combined
thermostat and thermal cut out device 110 and the other insulation wire 108(b) is
coupled to the thermal cut-out 108 of the combined thermostat and thermal cut out
device 110. The thermostat sensing bulb 106(a) and thermal cut-out sensing bulb
108(a) along with the spacer 109 are adapted to insert into the sensor tube 104 in
such a way that the thermostat sensing bulb 106(a) extends to the distal end of the
sensor tube 104 touching its one side surface 104(a) and the thermal cut-out sensing
bulb 108(a) lies below the thermostat sensing bulb 106(a) touching the other side
surface 104(b) of the sensor tube 104.
[0039] In an aspect, the spacer 109 binds the insulation wires (106(b) and 108(b))
together.
[0040] The arrangement and working of the water heating appliance 100 in
accordance with the present invention is as follows: The sensing bulbs (106(a) and
108(a)) along with the spacer 109 are adapted to insert into the sensor tube 104 in
such a way that the thermostat sensing bulb 106(a) extends to the distal end of the
sensor tube 104 touching its one side surface 104(a) and the thermal cut-out sensing
bulb 108(a) lies below the sensing bulb 106(a) touching the other side surface
104(b) of the sensor tube 104.
[0041] The heat from the heating element 102 gets transmitted to the sensor tube
104 through radiation and the heat from the sensor tube 104 in turn gets transmitted
to the sensing bulbs (106(a) and 108(a)) through conduction which ultimately
transmits the heat to the combined thermostat and thermal cut-out device 110
through the insulation wires (106(b) and 108(b)). The transmission of heat to the
combined thermostat and thermal cut-out device 110 facilitate the thermostat 106
and the thermal cut-out 108 in carrying out their respective function of tripping off.
[0042] In the preferred embodiment, the spacer 109 is made from thermoplastic
material.
[0043] The thermostat 106 and the thermal cut-out 108 can be digital as well as
mechanical devices.
[0044] It will be understood by those within the art that, in general, terms used
herein, and especially in the appended claims (e.g., bodies of the appended claims)
are generally intended as "open" terms (e.g., the term "including" should be
interpreted as "including but not limited to," the term "having" should be
interpreted as "having at least," the term "includes" should be interpreted as
"includes but is not limited to," etc.). It will be further understood by those within
the art that if a specific number of an introduced claim recitation is intended, such
an intent will be explicitly recited in the claim, and in the absence of such recitation
no such intent is present. For example, as an aid to understanding, the following
appended claims may contain usage of the introductory phrases "at least one" and
"one or more" to introduce claim recitations. However, the use of such phrases
should not be construed to imply that the introduction of a claim recitation by the
indefinite articles "a" or "an" limits any particular claim containing such introduced
claim recitation to inventions containing only one such recitation, even when the
same claim includes the introductory phrases "one or more" or "at least one" and
indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be
interpreted to mean "at least one" or "one or more"); the same holds true for the use
of definite articles used to introduce claim recitations. In addition, even if a specific
number of an introduced claim recitation is explicitly recited, those skilled in the
art will recognize that such recitation should typically be interpreted to mean at least
the recited number (e.g., the bare recitation of "two recitations," without other
modifiers, typically means at least two recitations, or two or more recitations).
Furthermore, in those instances where a convention analogous to "at least one of A,
B, and C, etc." is used, in general such a construction is intended in the sense one
having skill in the art would understand the convention (e.g., "a system having at
least one of A, B, and C" would include but not be limited to systems that have A
alone, B alone, C alone, A and B together, A and C together, B and C together,
and/or A, B, and C together, etc.). In those instances where a convention analogous
to "at least one of A, B, or C, etc." is used, in general such a construction is intended
in the sense one having skill in the art would understand the convention (e.g., "a
system having at least one of A, B, or C" would include but not be limited to systems
that have A alone, B alone, C alone, A and B together, A and C together, B and C
together, and/or A, B, and C together, etc.). It will be further understood by those
within the art that virtually any disjunctive word and/or phrase presenting two or
more alternative terms, whether in the description, claims, or drawings, should be
understood to contemplate the possibilities of including one of the terms, either of
the terms, or both terms. For example, the phrase "A or B" will be understood to
include the possibilities of "A" or "B" or "A and B."
[0045] It will be further appreciated that functions or structures of a plurality of
components or steps may be combined into a single component or step, or the
functions or structures of one-step or component may be split among plural steps
or components. The present invention contemplates all of these combinations.
Unless stated otherwise, dimensions and geometries of the various structures
depicted herein are not intended to be restrictive of the invention, and other
dimensions or geometries are possible. In addition, while a feature of the present
invention may have been described in the context of only one of the illustrated
embodiments, such feature may be combined with one or more other features of
other embodiments, for any given application. It will also be appreciated from the
above that the fabrication of the unique structures herein and the operation thereof
also constitute methods in accordance with the present invention. The present
invention also encompasses intermediate and end products resulting from the
practice of the methods herein. The use of "comprising" or "including" also
contemplates embodiments that "consist essentially of or "consist of the recited
feature.

WE CLAIM:
1. A water heating appliance (100), the appliance (100) comprising:
a sensor tube (104) mounted upright proximal to a heating element (102)
placed inside said water heating appliance (100); and
a combined thermostat and thermal cut-out device (110) placed inside said
water heating appliance (100) comprising: a thermostat sensing bulb
(106(a));
a thermal cut-out sensing bulb (108(a)); and
a spacer (109) wrapped around extending insulation wires (106(b) and
108(b)) of said sensing bulbs ((106(a) and 108(a)) placed against each other
at a predetermined location,
wherein said sensing bulbs ((106(a) and 108(a)) along with said spacer (109)
are adapted to insert into said sensor tube (104).
2. The water heating appliance (100) as claimed in claim 1, wherein said
thermostat sensing bulb (106(a)) is coupled to said thermostat (106) through
said insulation wire (106(b)) and said thermal cut-out sensing bulb (108(a))
is coupled to said thermal cut-out (108) through said insulation wire
(108(b)).
3. The water heating appliance (100) as claimed in claim 1, wherein said
thermostat sensing bulb (106(a)) extends to the distal end of said sensor tube
(104) in its assembled condition and said thermal cut-out sensing bulb
(108(a)) lies below said thermostat sensing bulb (106(a)) in its assembled
condition.
4. The water heating appliance (100) as claimed in claim 1, wherein said
thermostat sensing bulb (106(a)) touches on one side surface (104(a)) of
said sensor tube (104) and said thermal cut-out sensing bulb (108(a))
touches on the other side surface (104(b)) of said sensor tube (104).
5. The water heating appliance (100) as claimed in claim 1, wherein said
insulation wire (106(b)) at its one end (106(bl)) exists out of said spacer
(109).
6. The water heating appliance (100) as claimed in claim 1, wherein said
thermal cut-out sensing bulb (108(a)) rests over said spacer (109).
7. The water heating appliance (100) as claimed in claim 1, wherein said
heating element (102) and said sensor tube (104) are coated with scale
resistant material.
8. The water heating appliance (100) as claimed in claim 1, wherein said
heating element (102) and said sensor tube (104) are made of stainless steel
grade SS 316.
9. The water heating appliance (100) as claimed in claim 1, wherein said
spacer (109) is made from thermoplastic material.
10. The water heating appliance (100) as claimed in claim 1, wherein said
thermostat (106) and said thermal cut-out (108) are joined together through
fastening means.
11. The water heating appliance as claimed in claim 1, wherein said thermostat
(106) is mechanical and digital thermostat (106).
12. The water heating appliance as claimed in claim 1, wherein said thermal
cut-out (108) is mechanical and digital thermal cut-out (108).
13. The water heating appliance as claimed in claim 7, wherein the thickness of
the scale resistant material on said sensor tube (104) is 119 microns to 197
microns.