PTC thermistor element
By setting an insulating thermal conductivity film and a housing insulating film in the PTC thermistor element, combining the isolation frame and buffer layer, the problem that the PTC thermistor element in the prior art cannot take into account both insulation and thermal conductivity, and good insulation and thermal conductivity in the heater are achieved.
Patent Information
- Application Number
- CN202510660780.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2018-06-14
- Publication Date
- 2025-08-15
AI Technical Summary
When used in heaters, existing PTC thermistor components cannot take into account both insulation and thermal conductivity.
The structural design of the PTC thermistor layer, the positive electrode, the negative electrode, the first insulating thermal conduction film and the second insulating thermal conduction film are adopted. By providing an insulating thermal conduction film on both surfaces of the PTC thermistor layer and coating an insulating film on the surface of the shell, combining the isolation frame and the buffer layer, the balance between insulation and thermal conduction is achieved.
The PTC thermistor element has good insulation and thermal conductivity in the heater, and can efficiently transfer heat to the heater shell and control the heating temperature.
Smart Images
Figure CN120496977A_ABST
Abstract
Description
[0001] This application is a divisional application. The parent application is an invention patent application filed on June 14, 2018, with application number 201810615117.9 and the invention title “A PTC Thermistor Element.” Technical Field
[0002] The present invention relates to the technical field of PTC thermistors, in particular to a PTC thermistor element. Background Art
[0003] The heater is used for auxiliary heating of motor vehicles. It uses a PTC thermistor element for heating. However, the existing PTC thermistor element, when used in heaters, cannot achieve both good insulation and thermal conductivity. Summary of the Invention
[0004] An embodiment of the present invention provides a PTC thermistor element to solve the problem that the conventional PTC thermistor element cannot achieve both insulation and thermal conductivity when used in a heater.
[0005] An embodiment of the present invention provides a PTC thermistor element, comprising: a PTC thermistor layer, a positive electrode, a negative electrode, a first insulating thermally conductive film, and a second insulating thermally conductive film, wherein the PTC thermistor layer is electrically connected to the positive electrode and the negative electrode, respectively; and the first insulating thermally conductive film and the second insulating thermally conductive film are respectively disposed on two opposite surfaces of the PTC thermistor layer.
[0006] Furthermore, it also includes: a shell, the PTC thermistor layer, the positive electrode, the negative electrode, the first insulating thermally conductive film and the second insulating thermally conductive film are all located in the shell; the surface of the shell is coated with a first insulating film using a thermal spraying process or an oxidation process.
[0007] Furthermore: the thickness of the first insulating film is 0.01-0.5 mm.
[0008] Furthermore: the first insulating thermally conductive film and the second insulating thermally conductive film are both composed of a second insulating film and a thermally conductive silicone film, wherein the second insulating film is closer to the PTC thermistor layer than the thermally conductive silicone film.
[0009] Furthermore: the thickness of the second insulating film is 0.05-0.1 mm, and the thickness of the thermally conductive silicone film is 0.2-0.8 mm.
[0010] Furthermore: the first insulating heat-conductive film and the second insulating heat-conductive film are both silicone films with a fiber structure.
[0011] Furthermore: the thickness of the silicone membrane with fiber structure is 0.2 to 0.8 mm.
[0012] Further: the PTC thermistor layer is composed of multiple PTC thermistors, all of the PTC thermistors are divided into at least one group, the number of the positive electrode is one, the number of the negative electrodes is the same as the number of the groups of the PTC thermistors, each group of the PTC thermistors is electrically connected to the positive electrode, and each group of the PTC thermistors is electrically connected to each of the negative electrodes respectively; the positive electrode is located between the PTC thermistor layer and the first insulating thermally conductive film, and the negative electrode is located between the PTC thermistor layer and the second insulating thermally conductive film.
[0013] Further: the positive electrode and the negative electrode are both strip electrodes; the positive electrode is in a convex shape; if the number of the negative electrode is one, the negative electrode is in a convex shape; if the number of the negative electrodes is two or more, all the negative electrodes form a convex shape.
[0014] Furthermore, the invention further comprises: an isolation frame, wherein the isolation frame is divided into a plurality of blocks, and the PTC thermistor is arranged in the blocks of the isolation frame.
[0015] Furthermore, the maximum thickness of the isolation frame after thermal expansion is no greater than the thickness of the PTC thermistor layer.
[0016] Furthermore: the PTC thermistor layer, the first insulating thermally conductive film, the second insulating thermally conductive film and the isolation frame are all convex-shaped.
[0017] Furthermore, the method further includes: a buffer layer, which is arranged on a surface of the first insulating thermally conductive film that is separated from the PTC thermistor layer.
[0018] When the PTC thermistor element of the embodiment of the present invention is applied to a heater, the first insulating thermally conductive film and the second insulating thermally conductive film can play an insulating role to prevent the PTC thermistor layer from leaking electricity; at the same time, the first insulating thermally conductive film and the second insulating thermally conductive film can play a heat conducting role, thereby facilitating the efficient transfer of heat generated by the PTC thermistor to the housing of the heater, so that the heater can further transfer the heat to a desired location. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.
[0020] Figure 1is an exploded view of a PTC thermistor element according to an embodiment of the present invention;
[0021] Figure 2 is a three-dimensional diagram of a PTC thermistor element according to an embodiment of the present invention;
[0022] Figure 3 is a partial cross-sectional view of a PTC thermistor element according to an embodiment of the present invention;
[0023] Figure 4 FIG. 4 is a side view of a PTC thermistor element according to an embodiment of the present invention. DETAILED DESCRIPTION
[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.
[0025] The embodiment of the present invention provides a PTC thermistor element. The PTC thermistor element can be used for automobile heaters. Figures 1 to 4 As shown, the PTC thermistor element includes: a PTC thermistor layer 1, a positive electrode 2, a negative electrode 3, a first insulating thermally conductive film 4 and a second insulating thermally conductive film 5. The PTC thermistor layer 1 is electrically connected to the positive electrode 2 and the negative electrode 3 respectively, so that it can be heated by electricity. In addition, the heating temperature can be controlled by controlling the voltage of the positive electrode 2 and the negative electrode 3. Preferably, the connection terminals of the positive electrode 2 and the negative electrode 3 protrude from the PTC thermistor layer 1 so as to be electrically connected to an external controller, etc. Preferably, insulating rubber pads are arranged around the positive electrode 2 and the negative electrode 3 to avoid leakage. The first insulating thermally conductive film 4 and the second insulating thermally conductive film 5 are respectively arranged on the opposite surfaces of the PTC thermistor layer 1 and are in contact with the PTC thermistor layer 1. It should be understood that "element" here is only intended to represent an integral structure composed of several independent elements, and its specific form can be a device, etc.
[0026] When the PTC thermistor element is applied to a heater, the first insulating thermally conductive film 4 and the second insulating thermally conductive film 5 can play an insulating role to prevent the PTC thermistor layer 1 from leaking electricity. At the same time, the first insulating thermally conductive film 4 and the second insulating thermally conductive film 5 can play a heat conducting role to increase the heat conduction area, thereby facilitating the efficient transfer of heat generated by the PTC thermistor to the housing of the heater so that the heater can further transfer the heat to a desired location.
[0027] In a preferred embodiment, the thermistor element further includes a housing (not shown). The PTC thermistor layer 1, the positive electrode 2, the negative electrode 3, the first insulating thermally conductive film 4, and the second insulating thermally conductive film 5 are located within the housing. The surface of the housing is coated with a first insulating film using a thermal spraying or oxidation process. The first insulating film can be a ceramic film. The first insulating film provided on the surface of the housing further provides insulation. It should be understood that the first insulating film is generally applied to the inner surface of the housing; however, it can also be applied to both the inner and outer surfaces of the housing.
[0028] In a preferred embodiment, both the first insulating and thermally conductive film 4 and the second insulating and thermally conductive film 5 are composed of a second insulating film and a thermally conductive silicone film. The second insulating film can be a polyimide film. The second insulating film provides insulation and transfers heat to the thermally conductive silicone film; the thermally conductive silicone film provides efficient heat conduction, transferring heat to the heater housing. The insulating film is closer to the PTC thermistor layer 1 than the thermally conductive silicone film, forming a layered structure comprising, in order, the PTC thermistor layer 1, the second insulating film, and the thermally conductive silicone film. Preferably, the thickness of the second insulating film is 0.05-0.1 mm, and the thickness of the thermally conductive silicone film is 0.2-0.8 mm, thereby ensuring both insulation and efficient heat conduction. It should be understood that regardless of whether the PTC thermistor element includes the housing and the first insulating film thereon, or does not include the housing and the first insulating film thereon, the first insulating and thermally conductive film 4 and the second insulating and thermally conductive film 5 can have the aforementioned two-layer structure.
[0029] In another preferred embodiment, when the PTC thermistor element includes a housing, the first insulating and thermally conductive film 4 and the second insulating and thermally conductive film 5 can be a single-layer film structure. Specifically, the first insulating and thermally conductive film 4 and the second insulating and thermally conductive film 5 are both silicone films with a fiber structure. Due to their fiber structure, the silicone film with a fiber structure is stronger than pure silicone without a fiber structure and is less susceptible to damage and cracking. Furthermore, the silicone acts as an insulator. More preferably, the thickness of the silicone film with a fiber structure is 0.2 to 0.8 mm, which is more conducive to ensuring both insulation and efficient heat conduction.
[0030] Specifically, the PTC thermistor layer 1 is composed of multiple PTC thermistors. Specifically, the multiple PTC thermistors are arranged sequentially to form multiple rows and columns. The number of PTC thermistors is variable and can be set according to actual circumstances. Generally, as many as possible are arranged within a given area. In a preferred embodiment, the number of PTC thermistors is 44. The thickness of each PTC thermistor should be substantially consistent to avoid uneven contact between the PTC thermistor in certain locations and the first insulating and thermally conductive film 4 and / or the second insulating and thermally conductive film 5, which could lead to reduced heating efficiency or localized overheating.
[0031] All PTC thermistors are divided into at least one group. By grouping the PTC thermistors, each group of PTC thermistors can be controlled to be heated separately according to demand. The number of positive electrodes 2 is one, and the number of negative electrodes 3 is the same as the number of groups of PTC thermistors. Each group of PTC thermistors is electrically connected to the positive electrode 2, and each group of PTC thermistors is electrically connected to each negative electrode 3 respectively. For example, in a preferred embodiment, the PTC thermistors are grouped into three groups, each group containing at least one column of PTC thermistors. The number of negative electrodes 3 is three, namely a first negative electrode 31, a second negative electrode 32 and a third negative electrode 33 arranged in parallel. The first negative electrode 31, the second negative electrode 32 and the third negative electrode 33 are electrically connected to the three groups of PTC thermistors respectively.
[0032] Specifically, the positive electrode 2 is located between the PTC thermistor layer 1 and the first insulating thermally conductive film 4, and the negative electrode 3 is located between the PTC thermistor layer 1 and the second insulating thermally conductive film 5. For example, in a preferred embodiment, the first negative electrode 31, the second negative electrode 32, and the third negative electrode 33 are located between the PTC thermistor layer 1 and the second insulating thermally conductive film 5. Preferably, the positive electrode 2 and the negative electrode 3 are strip-shaped electrodes.
[0033] Specifically, the PTC thermistor element further includes: an isolation frame 6. It should be understood that the isolation frame 6 is located inside the shell. The isolation frame 6 is made of a heat-insulating material. The isolation frame 6 is divided into a plurality of blocks. The PTC thermistors are arranged in the blocks of the isolation frame 6. Preferably, the separated blocks can be strip blocks arranged in parallel, and each column of PTC thermistors is arranged in a strip block. Preferably, the separated blocks can be block blocks, and each PTC thermistor is arranged in a block block. It should be understood that the blocks can also be in other forms, and can be divided and arranged according to actual needs.
[0034] The maximum thickness of the isolation frame 6 after thermal expansion is no greater than the thickness of the PTC thermistor layer 1 , so as to prevent the positive electrode 2 , the negative electrode 3 from being separated from the PTC thermistor layer 1 .
[0035] Preferably, the PTC thermistor element further includes a buffer layer 7. It should be understood that the buffer layer 7 is located within the housing. The buffer layer 7 is disposed on the surface of the first insulating thermally conductive film 4 that is separated from the PTC thermistor layer 1. It should be understood that the first insulating thermally conductive film 4 has two opposing surfaces, one of which is opposite to the PTC thermistor layer 1, and the other is the surface separated from the PTC thermistor layer 1. The meaning of "separated" below is the same and will not be repeated. When the PTC thermistor element is disposed in a heater, when the heater is impacted, the housing will apply pressure to the PTC thermistor element. The buffer layer 7 can act as a buffer to prevent the PTC thermistor from being broken due to excessive instantaneous pressure. In addition, each PTC thermistor can be in contact with the housing, balancing the uneven thickness of the PTC thermistor and increasing the heat conduction area. The buffer layer 7 can be made of a compressed copper sheet, which has good thermal conductivity and ductility.
[0036] Preferably, when a PTC thermistor element is installed in a heater, its specific shape and structure can be adjusted according to the heater's layout. For example, when the heater is a water heater, it has water channels at the two corners of the housing. Therefore, fewer PTC thermistors can be installed at the corresponding positions of the PTC thermistor layer 1, so that the PTC thermistor layer 1 forms a convex shape. In a preferred embodiment, two fewer PTC thermistors can be installed at the corresponding positions of the PTC thermistor layer 1, i.e., at the two corners. Similarly, the shapes of the positive electrode 2, negative electrode 3, first insulating thermally conductive film 4, second insulating thermally conductive film 5, isolation frame 6, and buffer layer 7 are also adjusted accordingly. For example, the positive electrode 2, first insulating thermally conductive film 4, second insulating thermally conductive film 5, isolation frame 6, and buffer layer 7 are all convex. If there is only one negative electrode 3, then the negative electrode 3 has a convex shape; if there are two or more negative electrodes 3, then all negative electrodes 3 form a convex shape. For example, when there are three negative electrodes 3, the first negative electrode 31, the second negative electrode 32 and the third negative electrode 33 form a convex shape. It should be understood that the protruding ends of all the convex shapes are located at corresponding positions on the same side.
[0037] In summary, the PTC thermistor element of the embodiment of the present invention has good insulation and thermal conductivity, and can efficiently conduct heat to the housing of the heater; the heating temperature can be controlled by controlling the voltage and number of the PTC thermistors.
[0038] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0039] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they become aware of the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.
[0040] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.
[0041] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.
Claims
1. A PTC thermistor element, characterized in that: include: A PTC thermistor layer, a positive electrode, a negative electrode, a first insulating thermally conductive film and a second insulating thermally conductive film, wherein the PTC thermistor layer is electrically connected to the positive electrode and the negative electrode respectively; the first insulating thermally conductive film and the second insulating thermally conductive film are respectively arranged on two opposite surfaces of the PTC thermistor layer.
2. The PTC thermistor element according to claim 1, characterized in that: Also includes: a housing, wherein the PTC thermistor layer, the positive electrode, the negative electrode, the first insulating thermally conductive film, and the second insulating thermally conductive film are all located within the housing; The surface of the shell is coated with a first insulating film by using a thermal spraying process or an oxidation process.
3. The PTC thermistor element according to claim 2, wherein: The thickness of the first insulating film is 0.01 to 0.5 mm.
4. The PTC thermistor element according to claim 1 or 2, characterized in that: The first insulating thermally conductive film and the second insulating thermally conductive film are both composed of a second insulating film and a thermally conductive silicone film, wherein the second insulating film is closer to the PTC thermistor layer than the thermally conductive silicone film.
5. The PTC thermistor element according to claim 4, characterized in that: The thickness of the second insulating film is 0.05-0.1 mm, and the thickness of the thermally conductive silicone film is 0.2-0.8 mm.
6. The PTC thermistor element according to claim 2, wherein: The first insulating and heat-conductive film and the second insulating and heat-conductive film are both silicone films with a fiber structure.
7. The PTC thermistor element according to claim 6, characterized in that: The thickness of the silicone membrane with fiber structure is 0.2-0.8 mm.
8. The PTC thermistor element according to claim 1, wherein: The PTC thermistor layer is composed of multiple PTC thermistors, all of which are divided into at least one group. The number of positive electrodes is one, and the number of negative electrodes is the same as the number of groups of PTC thermistors. Each group of PTC thermistors is electrically connected to the positive electrode, and each group of PTC thermistors is electrically connected to each negative electrode respectively. The positive electrode is located between the PTC thermistor layer and the first insulating thermally conductive film, and the negative electrode is located between the PTC thermistor layer and the second insulating thermally conductive film.
9. The PTC thermistor element according to claim 8, characterized in that: Also includes: Isolation A frame, the isolation frame is divided into a plurality of blocks, and the PTC thermistor is arranged in the blocks of the isolation frame; The PTC thermistor layer, the first insulating heat-conductive film, the second insulating heat-conductive film and the isolation frame are all in a convex shape.
10. The PTC thermistor element according to claim 1, characterized in that: Also includes: A buffer layer is provided on a surface of the first insulating thermally conductive film that is separated from the PTC thermistor layer.