HEATING DEVICE FOR HOT WATER MAT

Information

  • Patent Application
  • 20170248324
  • Publication Number
    20170248324
  • Date Filed
    February 25, 2016
    8 years ago
  • Date Published
    August 31, 2017
    7 years ago
  • Inventors
  • Original Assignees
    • Eveli co., ltd.
Abstract
Provided is a heating device for a hot water mat that can minimize noise by a check valve for controlling flow of liquid. The heating device for a hot water mat includes: a water tank having a tub for keeping liquid and a discharge hole formed through a side of a lower portion to discharge the liquid in the tub; a heating module connected to the discharge hole and heating liquid; a separator disposed in the water tank, dividing the tub in to a first compartment at a lower portion and a second compartment at an upper portion, and having a connection hole for connecting the first compartment and the second compartment to each other; and a check valve disposed in the first compartment and opening and closing the connection hole by moving up and down by buoyancy from the liquid in the first compartment.
Description
BACKGROUND OF THE INVENTION

Field of the Invention


The present invention relates to a heating device for a hot water mat and, more particularly, a heating device for a hot water mat that can minimize noise by a check valve for controlling flow of liquid.


Description of the Related Art


An electric blanket or an electric mat that are used generally in winter can heat a portion of a floor or can achieve a heating effect for a short time, so they are generally used by many people.


However, electric wires are disposed in the electric blanket or the electric mat, so there is always a danger of an electric shock accident, harmful electronic waves are generated by their electric characteristics, and the harmful electronic waves are known as being harmful to a human body.


Accordingly, hot water mats employing the conventional On-Dol (underfloor heating) type and using hot water suitable for the features of Korea familiar with the On-Dol culture are recently on the market.


Hot water mats generally have circulation pipes uniformly arranged therein.


Those hot water mats have a liquid temperature controller such as a boiler and hot water heated by the liquid temperature controller heats the mats while flowing through the circulation pipes.


In general, a heating device for a hot water mat includes a heater, a water tank, and a check valve to heat circulation water, that is, liquid.


The check valve opens/closes a hole for supplying liquid into the water tank so that a predetermined amount of water is supplied to the heater through the water tank and liquid heated and expanded by the heater is supplied into the circulation pipes through the hole without leaking from the water tank.


Accordingly, liquid can be circulated and supplied to the mat through the circulation pipes by the check valve without need for a circulation pump.


There are various types of check valves and one type opens/closes a hole by moving up/down in accordance with water level in a water tank.


As a heating device for a hot water mat that uses such a floating type check valve, there is Korean Utility Model No. 20-0474868, titled “Hot water supply apparatus having check valve with improved molding property”.


In the “Hot water supply apparatus having check valve with improved molding property” disclosed in Korean Utility Model No. 20-0474868, a check valve for opening/closing a hole using buoyancy of liquid is horizontally moved, so it continuously generates shock noise that is unpleasant to a user's ears by hitting against other parts while horizontally moving.


Further, since the check valve is horizontally moved in the “Hot water supply apparatus having check valve with improved molding property” disclosed in Korean Utility Model No. 20-0474868, the check valve cannot open the hole in some cases due to dirt sticking to the valve.


If the check valve that is supposed to open the hole cannot open the hole, liquid in the water tank is not supplied to a heating module, an empty space is created in the heating module, the air in the space expands due to heating by the heater in the heating module and the check valve is pushed to the hole by the pressure of the expanding air, and accordingly, the check valve closes the hole rather than opens the hole. This is a reason for a poor product (hot water mat).


SUMMARY OF THE INVENTION

An object of the present invention is to provide a heating device for a hot water mat that can prevent shock noise due to a floatable check valve hitting against other parts while horizontally moving.


Another object of the present invention is to provide a heating device for a hot water mat in which when liquid decreases in a heating module, a hole is opened by a check valve and liquid is smoothly supplied by allowing the check valve to be freely moved up and down by buoyancy and its own weight to open/close so that the hole is prevented from not being opened.


A further object of the present invention is to provide a heating device for a hot water mat in which a heater and a sensor unit for heating liquid are easily and stably combined with a heater housing into a module.


In order to achieve the above objects, according to one aspect of the present invention, there is provided a heating device for a hot water mat that includes: a water tank having a tub for keeping liquid and a discharge hole formed through a side of a lower portion to discharge the liquid in the tub; a heating module connected to the discharge hole and heating liquid; a separator disposed in the water tank, dividing the tub in to a first compartment at a lower portion and a second compartment at an upper portion, and having a connection hole for connecting the first compartment and the second compartment to each other; and a check valve disposed in the first compartment and opening and closing the connection hole by moving up and down by buoyancy from the liquid in the first compartment.


The separator may have guide members protruding downward around the connection hole, and the check valve may include: a floater floated on liquid by buoyancy from the liquid in the first compartment; a packing member disposed on a top of the floater and opening and closing the connection hole by moving up and down with the floater; and a shock-absorbing member made of an elastic member, protruding outward farther than the floater, and first coming in contact with guide members when the check valve inside the guide members horizontally moves.


Guide protrusions inside which the check valve moves down protrude upward and are circumferentially arranged on a bottom of the first compartment.


The separator may have a hinge groove member protruding downward at a side of the connection hole, and the check valve may include: a floater floated on liquid by buoyancy from the liquid in the first compartment; a packing member disposed on a top of the floater and opening and closing the connection hole by moving up and down with the floater; and a hinge pin member protruding outward farther than the floater and rotatably coupled to the hinge groove member.


The heating module may include a heater housing, a heater disposed in the heater housing, and a sensor unit checking the state of the heater housing heated by the heater, the sensor unit may include a temperature sensor measuring temperature of the heater housing, a fuse disconnected when the temperature of the heater housing increases over a predetermined temperature, and a sensor housing made of synthetic resin and keeping the temperature sensor and the fuse, the fuse and the temperature sensor may be spaced and insulated from the heater housing by the sensor housing made of synthetic resin, and a separating portion made of synthetic resin for preventing contact between the temperature sensor and the fuse may be formed between the temperature sensor and the fuse in the sensor housing.


The heating module may include a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and an anti-vibration spring may be disposed between the first insertion hole and the heater.


The second insertion hole may be inclined with respect to a virtual liquid surface so that bubbles generated from liquid heated by the heater in the second insertion hole naturally flow to the first compartment of the water tank.


According to the heating device for a hot water mat of the present invention, the tub of the water tank is divided into the first compartment at the lower portion and the second compartment at the upper portion and the check valve opens/closes the connection hole connecting the first compartment and the second compartment by moving up/down by buoyancy from liquid, so when the liquid in the first compartment is insufficient, liquid is naturally supplied into the second compartment even without specific power, which is economical.


It is possible to prevent shock noise due to the floater hitting against the guide members, using the packing member (shock-absorbing member), when the check valve floated on the liquid in the first compartment horizontally moves.


Since the check valve opens the connection hole by moving down due to its own weight, it is possible to prevent the possibility of a defect of a product due to non-opening of the connection hole.


Since the heating module can be formed in a single unit by the heater, sensor unit, and heater housing, other parts can be easily assembled, so it is very useful for industrial development.





BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description when taken in conjunction with the accompanying drawings, in which:



FIG. 1 is a cross-sectional view of a heating device for a hot water mat according to an embodiment of the present invention;



FIG. 2 is a bottom perspective view of a separator according to an embodiment of the present invention;



FIG. 3 is a (horizontal) cross-sectional view taken along line A-A′ of FIG. 1;



FIGS. 4A and 4B are views for illustrating operation of the heating device for a hot water mat according to an embodiment of the present invention;



FIGS. 5A and 5B are a cross-sectional view and a view for illustrating operation of the heating device for a hot water mat according to another embodiment of the present invention;



FIG. 6 is a perspective view of a heating module according to the present invention;



FIG. 7 is an exploded perspective view of the heating module according to the present invention; and



FIG. 8 is a cross-sectional view taken along line B-B′ of FIG. 6.





DETAILED DESCRIPTION OF THE INVENTION

A heating device for a hot water mat according to the present invention is described hereafter in detail with reference to the drawings.


The present invention will now be described in detail based on aspects (or embodiments). The present invention may, however, be embodied in many different forms and should not be construed as being limited to only the embodiments set forth herein, but should be construed as covering modifications, equivalents or alternatives falling within ideas and technical scopes of the present invention. However, it is to be understood that the present invention is not limited to the specific exemplary embodiments, but includes all modifications, equivalents, and substitutions included in the spirit and the scope of the present invention.


In the figures, like reference numerals, particularly, reference numerals having the same last two digits or the same last two digits and letters refer to like elements having like functions throughout, and unless the context clearly indicates otherwise, elements referred to by reference numerals of the drawings should be understood based on this standard.


Also, for convenience of understanding of the elements, in the figures, sizes or thicknesses may be exaggerated to be large (or thick), may be expressed to be small (or thin) or may be simplified for clarity of illustration, but due to this, the protective scope of the present invention should not be interpreted narrowly.


The terminology used herein is for the purpose of describing particular aspects (or embodiments) only and is not intended to be limiting of the present invention. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” “comprising”, “includes” and/or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.


Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. It must be understood that the terms defined by the dictionary are identical with the meanings within the context of the related art, and they should not be ideally or excessively formally defined unless the context clearly dictates otherwise.


A heating device for a hot water mat according to the present invention, as shown in FIGS. 1 to 4B, includes a water tank 10, a separator 20, guide members 25, and a check valve 30.


The water tank 10 has a tub 11 for keeping liquid such as water.


A discharge hole 15 for discharging liquid in the tub 11 to a heating module 100 is formed through a side of the lower portion of the water tank 10.


The heating module 100 heats the liquid discharged through the discharge hole 15 so that the heated liquid circulates in a hot water mat.


The heating module 100 will be described in detail below.


The separator 20 is disposed in the water tank 10 and divides the tub 11 into an upper part and a lower part.


A first compartment 12 is formed under the separator 20 and a second compartment 13 is formed over the separator 20.


That is, the separator 20 divides the tub 11 into the first compartment 12 at the lower portion and the second compartment 13 at the upper portion.


The discharge hole 15 for discharging the liquid in the tub 11 to the heating module 100 is formed at a side of the first compartment 12.


Accordingly, the liquid in the first compartment 12 is heated by the heating module 100 connected through the discharge hole 15, so it increases in temperature higher than the liquid in the second compartment 13.


A connection hole 21 through which the liquid in the second compartment 13 flows into the first compartment 12 by connecting the first compartment 12 and the second compartment 13 is formed through the separator 20.


The guide members 25 protrude downward around the connection hole 21 from the separator 20.


The guide members 25 are made of plastic that is not deformed by the temperature of the liquid in the first compartment 12.


The guide members 25 are arranged with predetermined intervals around the connection hole 21.


Accordingly, liquid flows through the portions between the guide members 25 from the connection hole 21.


The check valve 30 is disposed inside the guide members 25 in the first compartment 12.


The check valve 30 opens/closes the connection hole 21 by being moved up/down by buoyancy of the liquid in the first compartment 12.


When the liquid in the first compartment 12 decreases or the liquid is completely discharged due to non-use for a long period of time and liquid is supplied into the first compartment 12 and the check valve 30 is moved up after the check valve 30 is moved down, if the check valve 30 comes out of the guide members 25 when moving down, it cannot be ensured that the check valve 30 comes back inside the guide members 25. Accordingly, guide protrusions 17 protruding upward are arranged circumferentially on the bottom of the first compartment 12 in the present invention so that the check valve 30 moves inside the guide protrusions 17 when moving down along the guide members 25, and the check valve 30 moves inside the guide members 25 when moving upward from the guide protrusions 17.


Further, when the separator 20 is combined with the water tank 10 in the process of assembling or maintaining the heating device, the check valve 30 can be inserted first inside the guide protrusions 17, so there is no need for combining the separator 20 with the water tank 10 with the check valve 30 inside the guide members 25.


The check valve 30 of the present invention includes a floater 31, a packing member 32, and a shock-absorbing member.


The floater 31 is partially floated on liquid by the buoyancy applied by the liquid in the first compartment 12.


The floater 31 is made of plastic that is not deformed by the temperature of the liquid in the first compartment 12.


The packing member 32 is made of rubber, sponge, or silicon, is disposed on the top of the floater 31, and opens/closes the bottom of the connection hole 21 by moving up/down with the floater 31.


If the packing member 32 is in contact with the bottom of the separator 20 around the connection hole 21 for a long period of time, it is stuck by the surface tension of the liquid, so it may not be detached even though the check valve 30 is supposed to move down using its own weight. Accordingly, by inclining the separator 20 around the connection hole 21 to reduce the contact area between the packing member 32 and the separator 20, it is possible to prevent the check valve 30 from not being detached from the connection hole. Further, the inclination allows bubbles in the liquid to easily pass through the connection hole 21, so noise is reduced.


The shock-absorbing member is made of an elastic material and protrudes outward farther than the floater 31.


The packing member 32 and the shock-absorbing member are made of a more flexible material than the floater 31.


The shock-absorbing member may be a part that is separate from the packing member 32 and combined with the floater 31, but in this embodiment, the packing member 32 is the shock-absorbing member.


That is, the packing member 32 and the shock-absorbing member are the same.


Accordingly, the packing member 32 is made of an elastic member and protrudes outward farther than the floater 31.


To this end, the packing member 32 that is combined with the floater 31 is wider than the floater 31 and protrudes outward farther than the floater 31.


According to this structure, when the check valve 30 inside the guide members 25 horizontally moves, the packing member 32 functioning as the shock-absorbing to member comes in contact with the guide members 25 earlier than the floater 31.


Accordingly, when the check valve 30 horizontally moves, not the floater 31 made of plastic, but the packing member 32 made of an elastic member comes in contact with the guide members 25 made of hard plastic, it is possible to prevent the floater 31 from generating noise by hitting against the guide members 25 when the check valve 30 horizontally moves.


The check valve 30 may further include an anti-tilting member 33 fitted around the lower portion of the floater 31 under the packing member 32.


The anti-tilting member 33 is made of a more flexible shock-absorbing material than the floater 31.


The anti-tilting member 33 may be an O-ring made of rubber.


The anti-tilting member 33 prevents the lower portion of the floater 31 from inclining when the check valve 30 horizontally moves and the packing member 32 at the top of the floater 31 comes in contact with the guide members 25, and it also prevents noise generated by the upper portion and the lower portion of the floater 31 coming in contact with the guide members 25 together with the packing member 32.


Operation of the present invention having the configuration described above is described hereafter with reference to FIGS. 4A and 4B.



FIG. 4A shows the state when the level of the liquid in the first compartment 12 is low and the connection hole 21 is open and FIG. 4B shows the state when liquid has flowed into the first compartment 12 through the connection hole 21 and the check valve 30 has closed the connection hole 21.


As shown in FIG. 4A, when the level of the liquid in the first compartment 12 is low, the check valve 30 moves down and the connection hole 21 is opened, so the first compartment 12 and the second compartment 13 communicate with each other.


When liquid is supplied into the second compartment 13 and the liquid flows into the first compartment 12 through the connection hole 21, the check valve 30 moves up inside the guide members 25.


The check valve 30 may horizontally move. Accordingly, when the check valve 30 horizontally moves, the packing member 32 protruding outward farther than the floater 31 first hits against the guide members 25, so it is possible to prevent shock noise from being generated due to hitting of the floater 31 and the guide members 25.


Further, the floater 31 is prevented from inclining by the anti-tilting member 33 fitted around the lower portion of the floater 31.


The floater 31, as described above, moves up in accordance with the level of the liquid flowing into the first compartment 12 without hitting against the guide members 25, so the packing member 32 closes the connection hole 21, as shown in FIG. 4B.


According to the present invention, it is possible to prevent noise that is unpleasant to a user's ears by minimizing noise that may be generated by the check valve 30 hitting against the guide members 25 when the check valve 30 moves up.



FIGS. 1 to 4B show that the check valve 30 is moved upward in the first compartment 12 by buoyancy and closes the connection hole 21.



FIGS. 5A and 5B show another embodiment of the present invention in which the check valve 30 opens/closes the connection hole 21 by turning about a side in the first compartment 12 by buoyancy.


Referring to FIGS. 5A and 5B, in order for the check valve 30 to turn about a side to open/close the connection hole 21, the separator 20 has a hinge groove member 27 protruding downward at a side of the connection hole 21 and the check valve 30 has a hinge pin member 37 protruding outward from the floater 31 and rotatably coupled to the hinge groove member 27.


Further, a sealing projection 28 with which the packing member 32 of the check valve 30 comes in contact is formed around the connection hole 21 of the separator 20.


The heating module 100 according to the present invention is described hereafter with reference to FIGS. 6 to 8.


The heating module 100 includes a heater housing 110, a heater 120, a sensor unit 130, and a coupling member.


The heater housing 110 has a first insertion hole 111 and a second insertion hole 112 longitudinally formed and spaced from each other.


The heater housing 110 is made of metal (for example, aluminum) and has the shape of a long rod.


The first insertion hole 111 and the second insertion hole 112 are formed at a predetermined distance from each other and are open at both sides in the heater housing 110.


Referring to FIG. 1, the second insertion hole 112 of the heater housing 110 that is connected to the first compartment 12 of the water tank 10 so that liquid flow through is formed at an angle to a virtual liquid surface so that bubbles generated in the second insertion hole 112 from liquid heated by the heater 120 naturally moves to the first compartment 12 of the water tank.


The virtual liquid surface is the surface of the liquid in the first compartment 12 and the angle is about 4 to 5 degrees.


Since the second insertion hole 112 is inclined at an angle of about 4 to 5 degrees, bubbles (air) from the liquid in the second insertion hole naturally flow into the first compartment 12 and the bubbles flowing in the first compartment 12 are discharged outside through the connection hole 21 when the check valve 30 moves down.


If the second insertion hole 112 is in parallel with the virtual liquid surface, the bubbles generated from the liquid in the second insertion hole 112 just move forward and backward in the second insertion hole 112, so they cause noise.


The heater 120 is inserted in the first insertion hole 111 and heats the heater housing 110.


As the heater 120 heats the heater housing 110, the heater housing 110 heats the liquid flowing from an end to the other end through the second insertion hole 112.


The heater 120 is a flat PTC heater and inserted in the first insertion hole 111.


In order to easily insert and fix the heater 120 in the first insertion hole 111, a bending portion 113 that bends toward the first insertion hole 111 is formed at both sides of the first insertion hole 111.


Accordingly, when pressure is applied to the top of the heater housing 110 with the heater 120 in the first insertion hole 111, the bending portions 113 are bent inward by the pressure and the height of the first insertion hole 111 decreases.


Accordingly, the heater 120 in the first insertion hole 111 is fixed to the heater housing 110 in the first insertion hole 111 under pressure.


A flat anti-vibration spring 119 is disposed between the first insertion hole 111 and the heater 120 to further fix the heater 120 with shaking under pressure.


The anti-vibration spring 119 has the shape of an arc of which the cross-section is curved upward or downward.


The sensor unit 130 is disposed between a pair of second locking steps 116.


The sensor unit 130 includes a temperature sensor 131, a fuse 132, and a sensor housing 133 keeping the temperature sensor 131 and the fuse 132.


The sensor housing 133 is made of synthetic resin that is an insulating material, and the temperature sensor 131 and the fuse 132 are inserted in holes formed in the sensor housing 133, respectively.


Accordingly, the sensor unit 130 with the temperature sensor 131 and the fuse 132 in the sensor housing 133 is inserted between the pair of second locking steps 116, so the assembly work is easy.


As shown in FIG. 6, a separating portion 134 is formed between the temperature sensor 131 and the fuse 132 in the sensor housing 133.


The temperature sensor 131 and the fuse 132 are separated from each other by the separating portion 134.


Since the temperature sensor 131 and the fuse 132 are separated by the separating portion 134 made of insulating synthetic resin, as described above, a short circuit due to contact between the temperature sensor 131 and the fuse 132 can be prevented.


The coupling member is a clip 141, which has a second elastic portion 143 at both sides that are separably locked to the second locking steps 116.


The ends of the second locking steps 116 are bent outward and the second elastic portions 143 are bent inward at both sides of the clip 141 to be locked to the ends of the second locking steps 116.


That is, the second locking steps 116 and the second elastic portions 143 are separably locked to each other like a hook.


The coupling member, that is, the clip 141 presses the sensor housing 133 between the second locking steps 116 to the heater housing 110.


In detail, as the second elastic portions 143 are locked to the second locking steps 116, the sensor unit 130 is fixed in close contact with the heater housing 110, inside the pair of locking steps 116, the clip 141, and the heater housing 110.


Although a heating device for a hot water mat that has a specific shape and structure was described above with reference to the accompanying drawings, the present invention may be changed and modified in various ways by those skilled in the art and those changes and modifications should be construed as being included in the scope of the present invention.

Claims
  • 1. A heating device for a hot water mat, comprising: a water tank having a tub for keeping liquid and a discharge hole formed through a side of a lower portion to discharge the liquid in the tub;a heating module connected to the discharge hole and heating liquid;a separator disposed in the water tank, dividing the tub in to a first compartment at a lower portion and a second compartment at an upper portion, and having a connection hole for connecting the first compartment and the second compartment to each other; anda check valve disposed in the first compartment and opening and closing the connection hole by moving up and down by buoyancy from the liquid in the first compartment.
  • 2. The heating device of claim 1, wherein the separator has guide members protruding downward around the connection hole, and the check valve includes:a floater floated on liquid by buoyancy from the liquid in the first compartment;a packing member disposed on a top of the floater and opening and closing the connection hole by moving up and down with the floater; anda shock-absorbing member made of an elastic member, protruding outward farther than the floater, and first coming in contact with guide members when the check valve inside the guide members horizontally moves.
  • 3. The heating device of claim 2, wherein guide protrusions inside which the check valve moves down protrude upward and are circumferentially arranged on a bottom of the first compartment.
  • 4. The heating device of claim 1, wherein the separator has a hinge groove member protruding downward at a side of the connection hole, and the check valve includes:a floater floated on liquid by buoyancy from the liquid in the first compartment;a packing member disposed on a top of the floater and opening and closing the connection hole by moving up and down with the floater; anda hinge pin member protruding outward farther than the floater and rotatably coupled to the hinge groove member.
  • 5. The heating device of claim 1, wherein the heating module includes a heater housing, a heater disposed in the heater housing, and a sensor unit checking the state of the heater housing heated by the heater, the sensor unit includes a temperature sensor measuring temperature of the heater housing, a fuse disconnected when the temperature of the heater housing increases over a predetermined temperature, and a sensor housing made of synthetic resin and keeping the temperature sensor and the fuse,the fuse and the temperature sensor are spaced and insulated from the heater housing by the sensor housing made of synthetic resin, anda separating portion made of synthetic resin for preventing contact between the temperature sensor and the fuse is formed between the temperature sensor and the fuse in the sensor housing.
  • 6. The heating device of claim 2, wherein the heating module includes a heater housing, a heater disposed in the heater housing, and a sensor unit checking the state of the heater housing heated by the heater, the sensor unit includes a temperature sensor measuring temperature of the heater housing, a fuse disconnected when the temperature of the heater housing increases over a predetermined temperature, and a sensor housing made of synthetic resin and keeping the temperature sensor and the fuse,the fuse and the temperature sensor are spaced and insulated from the heater housing by the sensor housing made of synthetic resin, anda separating portion made of synthetic resin for preventing contact between the temperature sensor and the fuse is formed between the temperature sensor and the fuse in the sensor housing.
  • 7. The heating device of claim 3, wherein the heating module includes a heater housing, a heater disposed in the heater housing, and a sensor unit checking the state of the heater housing heated by the heater, the sensor unit includes a temperature sensor measuring temperature of the heater housing, a fuse disconnected when the temperature of the heater housing increases over a predetermined temperature, and a sensor housing made of synthetic resin and keeping the temperature sensor and the fuse,the fuse and the temperature sensor are spaced and insulated from the heater housing by the sensor housing made of synthetic resin, anda separating portion made of synthetic resin for preventing contact between the temperature sensor and the fuse is formed between the temperature sensor and the fuse in the sensor housing.
  • 8. The heating device of claim 4, wherein the heating module includes a heater housing, a heater disposed in the heater housing, and a sensor unit checking the state of the heater housing heated by the heater, the sensor unit includes a temperature sensor measuring temperature of the heater housing, a fuse disconnected when the temperature of the heater housing increases over a predetermined temperature, and a sensor housing made of synthetic resin and keeping the temperature sensor and the fuse,the fuse and the temperature sensor are spaced and insulated from the heater housing by the sensor housing made of synthetic resin, anda separating portion made of synthetic resin for preventing contact between the temperature sensor and the fuse is formed between the temperature sensor and the fuse in the sensor housing.
  • 9. The heating device of claim 1, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and an anti-vibration spring is disposed between the first insertion hole and the heater.
  • 10. The heating device of claim 2, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and an anti-vibration spring is disposed between the first insertion hole and the heater.
  • 11. The heating device of claim 3, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and an anti-vibration spring is disposed between the first insertion hole and the heater.
  • 12. The heating device of claim 4, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and an anti-vibration spring is disposed between the first insertion hole and the heater.
  • 13. The heating device of claim 1, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and the second insertion hole is inclined with respect to a virtual liquid surface so that bubbles generated from liquid heated by the heater in the second insertion hole naturally flow to the first compartment of the water tank.
  • 14. The heating device of claim 2, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and the second insertion hole is inclined with respect to a virtual liquid surface so that bubbles generated from liquid heated by the heater in the second insertion hole naturally flow to the first compartment of the water tank.
  • 15. The heating device of claim 3, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and the second insertion hole is inclined with respect to a virtual liquid surface so that bubbles generated from liquid heated by the heater in the second insertion hole naturally flow to the first compartment of the water tank.
  • 16. The heating device of claim 4, wherein the heating module includes a heater and a heater housing having a first insertion hole for inserting the heater and a second insertion hole through which liquid discharged from the water tank flow, in which the first insertion hole and the second insertion hole are spaced from each other, and the second insertion hole is inclined with respect to a virtual liquid surface so that bubbles generated from liquid heated by the heater in the second insertion hole naturally flow to the first compartment of the water tank.