(19)
(11) EP 4 029 387 A1

(12) EUROPEAN PATENT APPLICATION
published in accordance with Art. 153(4) EPC

(43) Date of publication:
20.07.2022 Bulletin 2022/29

(21) Application number: 20864225.6

(22) Date of filing: 09.09.2020
(51) International Patent Classification (IPC): 
A24F 40/40(2020.01)
H05B 3/03(2006.01)
A24F 40/46(2020.01)
(52) Cooperative Patent Classification (CPC):
A24F 40/40; A24F 40/50; A24F 40/51; A24F 40/46; H05B 1/02; H05B 3/02; H05B 3/03
(86) International application number:
PCT/CN2020/114231
(87) International publication number:
WO 2021/047543 (18.03.2021 Gazette 2021/11)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
KH MA MD TN

(30) Priority: 09.09.2019 CN 201910847206

(71) Applicant: China Tobacco Hubei Industrial Corporation Limited
Dongxihu District Wuhan Hubei 430040 (CN)

(72) Inventors:
  • LI, Dan
    Wuhan, Hubei 430040 (CN)
  • LIU, Huachen
    Wuhan, Hubei 430040 (CN)
  • HUANG, Ting
    Wuhan, Hubei 430040 (CN)
  • CHEN, Yikun
    Wuhan, Hubei 430040 (CN)

(74) Representative: Garavelli, Paolo 
A.BRE.MAR. S.R.L. Consulenza in Proprietà Industriale Via Servais 27
10146 Torino
10146 Torino (IT)

   


(54) HEATER AND ELECTRIC HEATING SYSTEM USING HEATER


(57) Embodiments provide a heater and an electric heating system using the same. In the embodiments, the heater includes a heating element for heating tobacco products to generate aerosol, and a plurality of heating resistors are arranged at intervals on the heating element The two ends of each of the heating resistors are respectively connected to the electrode part, and the free end of the electrode part is used to connect the heat source part; wherein, a plurality of the heating resistors operate sequentially or together to generate heat. The electrical heating system of the present disclosure includes a heater receiving part containing the heater for heating the tobacco product to generate the aerosol. The present disclosure can improve the overall heating speed of the heating element and improve the heating uniformity.




Description

TECHNICAL FIELD



[0001] The present disclosure relates to a heater and an electric heating system using the heater.

BACKGROUND



[0002] The heater is activated for the entire smoking session or the heater is activated every time the user puffs. The heating element used in the existing aerosol generation system is made of a thermally conductive material such as a ceramic material, and a heating resistor structure is usually provided outside the thermally conductive material. The heating resistor structure can be provided in the form of a heating wire or a circuit substrate, etc., and is connected with electrical leads that transmit electrical energy from the power source to the heating resistor structure and then to the heating element. Since the heater is one of the core components of the aerosol generation system, its process and function have a key impact on the aerosol generation system. However, the design of the external heating resistance structure adopted by the existing heating element makes the heat transfer path single, leading to the problems of slow heating speed and poor heating uniformity of the heating element.

SUMMARY



[0003] In view of the above problems, the present disclosure is intended to provide a heater, a heating system and a tobacco product using the heater, such that the overall heating speed of the heating element and the heating uniformity can be improved.

[0004] In order to achieve the above object, in one aspect, the present disclosure provides a heater, comprising a heating element for heating a tobacco product to generate aerosol, the heating element being provided with a plurality of heating resistors at intervals, each of two ends of each of the plurality of heating resistors being connected with an electrode part, respectively, and a free end of the electrode part being configured for connecting a heat source part; wherein, the plurality of the heating resistors operate sequentially or together to generate heat.

[0005] In an embodiment, the electrode part comprises a first electrode and a plurality of second electrodes; a first end of each of the heating resistors is commonly connected to the first electrode through an electrical lead; a second end of the each of the heating resistors is respectively connected to each of the second electrodes through the electrical lead.

[0006] In an embodiment, the electrode part comprises a plurality of third electrodes and a plurality of fourth electrodes; a first end of the each of the heating resistors is respectively connected to each of the third electrodes through the electrical lead, a second end of the each of the heating resistors is respectively connected to each of the fourth electrodes through the electrical lead.

[0007] In an embodiment, the plurality of the heating resistors are provided at intervals between a first end of the heating element and a second end of the heating element; wherein the first end of the heating element is configured for contacting an initial section of the tobacco product, and the second end of the heating element is configured for contacting a middle and a rear sections of the tobacco product.

[0008] In an embodiment, when the each of the heating resistors is connected to the heat source part through the electrode part, the each of the heating resistors is activated, and operates in a working state or in a sleep state.

[0009] In an embodiment, the each of the heating resistors located at both the first end and the second end of the heating element is activated.

[0010] In an embodiment, the each of the heating resistors located at the first end of the heating element is in the working state, and the each of the heating resistors located at the second end of the heating element is in the sleep state; or the each of the heating resistors located at the second end of the heating element is in the working state, and the each of the heating resistors located at the first end of the heating element is in the sleep state.

[0011] In an embodiment, the each of the heating resistors located at the first end and the second end of the heating element is in an alternate working state.

[0012] In an embodiment, the each of the heating resistors located at the first end and the second end of the heating element is in a co-working state.

[0013] In an embodiment, the each of the heating resistors located at the first end of the heating element is activated, and the each of the heating resistors located at the second end of the heating element is deactivated; or the each of the heating resistors at the second end of the heating element is activated, and the each of the heating resistors at the first end of the heating element is deactivated.

[0014] In an embodiment, the each of the heating resistors is respectively connected with a temperature control sensor, for monitoring a temperature value of the each of the heating resistors in real time.

[0015] In an embodiment, when the temperature control sensor detects that the each of the heating resistors located at the first end of the heating element reaches a preheating temperature, the each of the heating resistors located at the second end of the heating element is activated for preheating; or when the temperature control sensor detects that the each of the heating resistors located at the second end of the heating element reaches the preheating temperature, the each of the heating resistors located at the first end of the heating element is activated for preheating.

[0016] In an embodiment, the each of the heating resistors is respectively connected to a timer, for turning on or off the each of the heating resistors regularly.

[0017] In an embodiment, when the timer turns on the each of the heating resistors regularly, the each of the heating resistors is in the working state regularly; or when the timer turns off the each of the heating resistors regularly, the each of the heating resistors is in the sleep state regularly.

[0018] In an embodiment, the each of the heating resistors is coated, bonded or combined on the heating element, respectively.

[0019] In an embodiment, the heating element is made of a thermally conductive material.

[0020] In an embodiment, the heating element is made of a ceramic material.

[0021] In an embodiment, the heating element is one selected from a group consisting of a needle heating element, an elliptical cylindrical heating element, a conical heating element, a cylindrical heating element and a prismatic heating element.

[0022] In an embodiment, the heat source part is a power source.

[0023] In other aspect, the present disclosure provides an electric heating system comprising a heater receiving part configured for receiving the heater, for heating the tobacco product to generate aerosol.

[0024] In an embodiment, a plurality of the heating resistors are respectively connected to a heat source part through the electrode part, and the heater is configured for heating the tobacco product to generate the aerosol.

[0025] In an embodiment, when the first electrode is connected to the heat source part, and each of the second electrodes is connected to the heat source part, the each of the heating resistors located at the first end or the second end of the heating element is activated; or when the first electrode is connected to the heat source part, and the each of the heating resistors located at the first end or the second end of the heating element is connected to the heat source part through the second electrode, the each of the heating resistors located at the first end or the second end of the heating element is activated.

[0026] In an embodiment, when each of the third electrodes is connected to the heat source part, and each of the fourth electrodes is connected to the heat source part, the each of the heating resistors located at the first end and the second end of the heating element is activated; or when the each of the heating resistors located at the first end or the second end of the heating element is connected to the heat source through the third electrode and the fourth electrode, respectively, the each of the heating resistors located at the first end or the second end of the heating element is activated.

[0027] The present disclosure has the following advantages due to the adoption of the above technical solutions:
  1. 1. The present disclosure is provided with a plurality of heating resistors, and the plurality of heating resistors can operate sequentially or together to generate heat, and quickly transfer the heat to the heating element, so that the overall heating speed of the heating element can be improved and the heating uniformity can be good.
  2. 2. The present disclosure is provided with a first electrode and a plurality of second electrodes, which can facilitate the activation of the heating resistors located at the first end and/or the second end of the heating element, with good flexibility and good controllability.
  3. 3. The present disclosure is provided with a first electrode, and the first ends of the plurality of heating resistors share the first electrode, which can improve the space utilization rate of the structure.
  4. 4. The present disclosure is provided with a plurality of third electrodes and a plurality of fourth electrodes, which can facilitate the activation of the heating resistors located at the first end and/or the second end of the heating element, with good flexibility and good controllability.
  5. 5. The heating resistors at the first end and the second end of the heating element of the present disclosure can be in an alternate working state, such that the first end and the second end of the heating element can be alternately heated, and the overall heating speed and heating uniformity of the heating element can be further improved, with good flexibility, it is simple and efficient.
  6. 6. The present disclosure is provided with a temperature control sensor, which can further improve the heating speed and heating uniformity of the heating element, and has good temperature control.
  7. 7. The present disclosure is provided with a timer, which can precisely control the working time or sleep time of the heating resistors, so that the heating uniformity of the heating element is further improved.
  8. 8. The present disclosure has the advantages of simple structure, convenient use and broad market prospect.


[0028] Other features and advantages of the present disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present disclosure. The objectives and other advantages of the present disclosure may be realized and attained by the structure particularly pointed out in the description, claims and drawings.

BRIEF DESCRIPTION OF DRAWINGS



[0029] In order to illustrate the technical solutions in the embodiments of the present disclosure more clearly, the following briefly introduces the accompanying drawings required in the description of the embodiments:

FIG. 1 is a schematic structural diagram illustrating a heater of a first embodiment according to the present disclosure;

FIG. 2 is a schematic diagram illustrating a circuit coating structure of the heater of the first embodiment according to the present disclosure;

FIG. 3 is a schematic structural diagram illustrating the heater of a second embodiment according to the present disclosure;

FIG. 4 is a schematic diagram illustrating the circuit coating structure of the heater of the second embodiment according to the present disclosure.


DESCRIPTION OF EMBODIMENTS



[0030] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings and examples, so as to fully understand and implement the implementation process of how the present disclosure applies technical means to solve technical problems and achieve technical effects. It should be noted that, as long as there is no conflict, each embodiment of the present disclosure and each feature of each embodiment can be combined with each other, and the formed technical solutions all fall within the protection scope of the present disclosure.

[0031] As shown in FIGS. 1 and 2, the heater provided in the first embodiment of the present disclosure includes a heating element 1 for heating tobacco products to generate aerosol, two heating resistors 2 are arranged on the heating element 1 at intervals, two ends of each heating resistor 2 are connected to an electrode part 3 respectively, and the free ends of the electrode part 3 are used to connect to the heat source part. When the free end of the electrode part 3 is connected to the heat source part, the two heating resistors 2 can operate successively or jointly to generate heat, and quickly transfer the heat to the heating element 1, so that the overall heating speed of the heating element 1 is improved and the heating uniformity is good.

[0032] Further, the electrode part 3 includes a first electrode 31 and two second electrodes 32. The first ends of the two heating resistors 2 are jointly connected to the first electrode 31 through the electrical lead 4, and the second ends of the two heating resistors 2 are respectively connected to a second electrode 32 through the electrical lead 4. The first ends of the two heating resistors 2 share the first electrode 31, which can improve the space utilization rate of the structure.

[0033] Further, the two heating resistors 2 are arranged at intervals between the first end of the heating element 1 and the second end of the heating element 1. Wherein, the first end of the heating element 1 is used to contact the initial section of the tobacco product, and the second end of the heating element 1 is used to contact the middle and rear sections of the tobacco product.

[0034] Further, when each heating resistor 2 is connected to the heat source part through the electrode part 3, the each heating resistor 2 is activated, and the each heating resistor 2 operates in the working state and the sleep state after being activated.

[0035] Further, both the heating resistors 2 located at the first end and the second end of the heating element 1 are activated.

[0036] Further, the heating resistor 2 located at the first end of the heating element 1 is in the working state, while the heating resistor 2 located at the second end of the heating element 1 is in the sleep state; or the heating resistor 2 located at the second end of the heating element 1 is in the working state, while the heating resistor 2 located at the first end of the heating element 1 is in the sleep state. Specifically, the heating resistor 2 located at the first end of the heating element 1 is in the working state, while the heating resistor 2 located at the second end of the heating element 1 is in the sleep state, that is, the heating resistor 2 located at the second end of the heating element 1 is only in an activated but inactive state (standby state). Alternatively, the heating resistor 2 located at the second end of the heating element 1 is in the working state, while the heating resistor 2 located at the first end of the heating element 1 is in the sleep state, that is, the heating resistor 2 located at the first end of the heating element 1 is only in an activated but inactive state (standby state). Therefore, according to actual needs, the heating resistor 2 at the first end of the heating element 1 can be activated for a period of time, and then the heating resistor 2 at the second end of the heating element 1 can be activated. Alternatively, the heating resistor 2 at the second end of the heating element 1 can be activated first for a period of time, and then the heating resistor 2 at the first end of the heating element 1 is activated. For example, when the heating element 1 is started, the heating resistor 2 located at the first end of the heating element 1 is first activated for a period of time, for example, 30 seconds, so that the first end of the heating element 1 is sufficiently preheated and the aerosol can be volatilized, and then the heating resistor 2 at the second end of the heating element 1 is activated for a period of time such as 30 seconds, so that the second end of the heating element 1 is sufficiently preheated and can start to volatilize the aerosol. By activating the two heating resistors 2 at different positions of the heating element 1 successively, the first end and the second end of the heating element 1 can be heated successively. The heating resistors 2 located at the first end and the second end of the heating element 1 are in an alternate working state, that is, the first end and the second end of the heating element 1 are alternately heated, which can further improve the overall heating speed and heating uniformity of the heating element 1, with good flexibility, simplicity and efficiency.

[0037] Further, the heating resistors 2 located at the first end and the second end of the heating element 1 are both in working state. Specifically, the heating resistor 2 located at the first end of the heating element 1 is activated to operate, and the heating resistor 2 located at the second end of the heating element 1 is also activated to operate. Alternatively, the heating resistor 2 located at the second end of the heating element 1 is activated to operate, and the heating resistor 2 located at the first end of the heating element 1 is also activated to operate. By activating the two heating resistors 2 at the first end and the second end of the heating element 1 and making them operate together, the heating speed and the overall heating uniformity of the heating element 1 can be further improved. To sum up, when the heating resistor 2 located in a certain area of the heating element 1 is activated to operate, the heating resistor 2 located in another area of the heating element 1 may be in a working state or the sleep state. Moreover, the heating resistor 2 located in a certain area of the heating element 1 can be activated to operate for a period of time, or can be continuously in the working state. The heating resistors 2 located in a certain area of the heating element 1 and the heating resistors 2 located in another area of the heating element 1 can operate sequentially or simultaneously.

[0038] Further, the heating resistor 2 located at the first end of the heating element 1 is activated, while the heating resistor 2 located at the second end of the heating element 1 is not activated; alternatively, the heating resistor 2 located at the second end of the heating element 1 is activated, but the heating resistor 2 located at the first end of the heating element 1 is not activated, it is convenient to use and has good flexibility.

[0039] Further, the two heating resistors 2 are respectively connected with temperature control sensors for monitoring the temperature value of the heating resistors 2 in real time.

[0040] Further, when the temperature control sensor detects that the heating resistor 2 at the first end of the heating element 1 reaches the preheating temperature, and then activates the heating resistor 2 at the second end of the heating element 1 for preheating. Alternatively, when the temperature control sensor detects that the heating resistor 2 at the second end of the heating element 1 reaches the preheating temperature, and then activates the heating resistor 2 at the first end of the heating element 1 for preheating. Through the temperature control sensor, the heating speed and heating uniformity of the heating element 1 can be further improved, and the temperature controllability is good.

[0041] Further, the two heating resistors 2 are respectively connected to timers for timing on or off the heating resistors.

[0042] Further, when the timer turns on the heating resistor 2 regularly, the heating resistor 2 operates regularly, and after a period of time, the tobacco products are prompted to start emitting aerosols. Alternatively, when the timer turns off the heating resistor 2 regularly, the heating resistor 2 is made to sleep regularly. The working time or sleep time of the heating resistors 2 can be precisely controlled by the timer.

[0043] Further, the two heating resistors 2 are respectively coated, bonded or combined on the heating element 1.

[0044] Further, the heating element 1 is made of thermally conductive material.

[0045] Further, the heating element 1 is made of ceramic material.

[0046] Further, the heat source part is a power source.

[0047] Further, the heating element can be a needle heating element, or an elliptical cylindrical heating element, or a conical heating element, or a cylindrical heating element or a prismatic heating element.

[0048] When in use, when the first electrode 31 and the two second electrodes 32 are respectively powered on, the heating resistor 2 at the first end of the heating element 1 and the heating resistor 2 at the second end are activated to operate together to generate heat. The heat is transferred to the heating element 1, achieving uniformity of the overall heating of the heating element 1.

[0049] On the basis of the above-mentioned first embodiment, as shown in FIGS. 3 and 4, the heater provided in the second embodiment of the present disclosure is different from the first embodiment in that the electrode part 3 includes two third electrodes 33 and two fourth electrodes 33. The first ends of the two heating resistors 2 are respectively connected to the third electrodes 33 through electrical leads 4, the second ends of the two heating resistors 2 are respectively connected to the fourth electrodes 34 through the electrical leads 4. The reliability of the circuit can be improved through the two third electrodes 33 and the two fourth electrodes 34.

[0050] When in use, when the heating resistor 2 located at the first end of the heating element 1 is connected to the heat source part through the third electrode 33 and the fourth electrode 34, respectively, the heating resistor 2 located at the first end of the heating element 1 is activated to operate, to realize the preheating of the heating element 1 for a period of time. Then, the heating resistor 2 located at the second end of the heating element 1 is connected to the heat source part through the third electrode 33 and the fourth electrode 34, respectively, so that the heating resistor 2 located at the second end of the heating element 1 is activated. At this time, the heating resistor 2 located at the first end of the heating element 1 may be in a working state or the sleep state. The heating resistor 2 located at the second end of the heating element 1 can work for a period of time or in a continuous working state. And the heating resistors 2 located at the first end and the second end of the heating element 1 can be in an alternate or simultaneous working state. Therefore, the heating resistors 2 are respectively provided at the first end and the second end of the heating element 1, which can improve the overall heating speed of the heating element 1 and improve the heating uniformity.

[0051] On the basis of the above heater, in another aspect, the electric heating system provided by the present disclosure includes a heater receiving part, and the heater receiving part accommodates the above-mentioned heater for heating tobacco products to generate aerosol.

[0052] In a specific embodiment, the plurality of heating resistors 2 are connected to the heat source part through the electrode part 3. Heaters are used to heat tobacco products to generate aerosols.

[0053] In a specific embodiment, when the first electrode 31 is connected to the heat source part, and the two second electrodes 32 are both connected to the heat source part, the heating resistors 2 located at the first end and the second end of the heating element 1 are both activated. Alternatively, when the first electrode 31 is connected to the heat source part, and the heating resistor 2 located at the first end or the second end of the heating element 1 is connected to the heat source part through the second electrode 32, the heating resistor 2 at the first end or the second end of the heating element 1 is activated.

[0054] In a specific embodiment, when the two third electrodes 33 are both connected to the heat source part, and the two fourth electrodes 34 are both connected to the heat source part, the heating resistors 2 located at the first end and the second end of the heating element 1 are both activated. Alternatively, when the heating resistor 2 located at the first end or the second end of the heating element 1 is connected to the heat source part through the third electrode 33 and the fourth electrode 34, respectively, the heating resistor body 2 located at the first end or the second end of the heating element 1 is activated.

[0055] Although the disclosed embodiments of the present disclosure are shown as above, the content described is only embodiments adopted to facilitate understanding of the present disclosure, and is not intended to limit the present disclosure. Any person skilled in the art to which the present disclosure belongs, without departing from the spirit and scope disclosed by the present disclosure, can make any modifications and changes in the form and details of the implementation, but the scope of patent protection of the present disclosure shall still be subject to the scope defined by the appended claims.


Claims

1. A heater, comprising a heating element for heating a tobacco product to generate aerosol, the heating element being provided with a plurality of heating resistors at intervals, each of two ends of each of the plurality of heating resistors being connected with an electrode part, respectively, and a free end of the electrode part being configured for connecting a heat source part;
wherein, the plurality of the heating resistors operate sequentially or together to generate heat.
 
2. The heater according to claim 1, wherein the electrode part comprises a first electrode and a plurality of second electrodes; a first end of each of the heating resistors is commonly connected to the first electrode through an electrical lead; a second end of the each of the heating resistors is respectively connected to each of the second electrodes through the electrical lead.
 
3. The heater according to claim 1, wherein the electrode part comprises a plurality of third electrodes and a plurality of fourth electrodes; a first end of the each of the heating resistors is respectively connected to each of the third electrodes through the electrical lead, a second end of the each of the heating resistors is respectively connected to each of the fourth electrodes through the electrical lead.
 
4. The heater according to claim 1, wherein the plurality of the heating resistors are provided at intervals between a first end of the heating element and a second end of the heating element; wherein the first end of the heating element is configured for contacting an initial section of the tobacco product, and the second end of the heating element is configured for contacting a middle and a rear sections of the tobacco product.
 
5. The heater according to claim 4, wherein when the each of the heating resistors is connected to the heat source part through the electrode part, the each of the heating resistors is activated, and operates in a working state or in a sleep state.
 
6. The heater according to claim 5, wherein the each of the heating resistors located at both the first end and the second end of the heating element is activated.
 
7. The heater according to claim 6, wherein the each of the heating resistors located at the first end of the heating element is in the working state, and the each of the heating resistors located at the second end of the heating element is in the sleep state; or
the each of the heating resistors located at the second end of the heating element is in the working state, and the each of the heating resistors located at the first end of the heating element is in the sleep state.
 
8. The heater according to claim 7, wherein the each of the heating resistors located at the first end and the second end of the heating element is in an alternate working state.
 
9. The heater according to claim 6, wherein the each of the heating resistors located at the first end and the second end of the heating element is in a co-working state.
 
10. The heater according to claim 5, wherein the each of the heating resistors located at the first end of the heating element is activated, and the each of the heating resistors located at the second end of the heating element is deactivated; or
the each of the heating resistors at the second end of the heating element is activated, and the each of the heating resistors at the first end of the heating element is deactivated.
 
11. The heater according to claim 5, wherein the each of the heating resistors is respectively connected with a temperature control sensor, for monitoring a temperature value of the each of the heating resistors in real time.
 
12. The heater according to claim 11, wherein when the temperature control sensor detects that the each of the heating resistors located at the first end of the heating element reaches a preheating temperature, the each of the heating resistors located at the second end of the heating element is activated for preheating; or
when the temperature control sensor detects that the each of the heating resistors located at the second end of the heating element reaches the preheating temperature, the each of the heating resistors located at the first end of the heating element is activated for preheating.
 
13. The heater according to claim 5, wherein the each of the heating resistors is respectively connected to a timer, for turning on or off the each of the heating resistors regularly.
 
14. The heater according to claim 13, wherein when the timer turns on the each of the heating resistors regularly, the each of the heating resistors is in the working state regularly; or
when the timer turns off the each of the heating resistors regularly, the each of the heating resistors is in the sleep state regularly.
 
15. The heater according to claim 1, wherein the each of the heating resistors is coated, bonded or combined on the heating element, respectively.
 
16. The heater according to claim 1, wherein the heating element is made of a thermally conductive material.
 
17. The heater according to claim 16, wherein the heating element is made of a ceramic material.
 
18. The heater according to claim 1, wherein the heating element is one selected from a group consisting of a needle heating element, an elliptical cylindrical heating element, a conical heating element, a cylindrical heating element and a prismatic heating element.
 
19. The heater according to claim 1, wherein the heat source part is a power source.
 
20. An electric heating system comprising a heater receiving part configured for receiving the heater according to any one of claims 1-19, for heating a tobacco product to generate aerosol.
 
21. The electric heating system according to claim 20, wherein a plurality of the heating resistors are respectively connected to a heat source part through the electrode part, and the heater is configured for heating the tobacco product to generate the aerosol.
 
22. The electric heating system according to claim 21, wherein when the first electrode is connected to the heat source part, and each of the second electrodes is connected to the heat source part, the each of the heating resistors located at the first end and the second end of the heating element is activated; or
when the first electrode is connected to the heat source part, and the each of the heating resistors located at the first end or the second end of the heating element is connected to the heat source part through the second electrode, the each of the heating resistors located at the first end or the second end of the heating element is activated.
 
23. The heating system according to claim 21, wherein when each of the third electrodes is connected to the heat source part, and each of the fourth electrodes is connected to the heat source part, the each of the heating resistors located at the first end or the second end of the heating element is activated; or
when the each of the heating resistors located at the first end or the second end of the heating element is connected to the heat source through the third electrode and the fourth electrode, respectively, the each of the heating resistors located at the first end or the second end of the heating element is activated.
 




Drawing
















Search report