Compact thick film heater
By designing the rectangular structure and partition plate settings of compact thick film heaters, the problems of low space utilization and many welding parts of traditional heaters are solved, and higher space utilization, lower weight and cost, as well as higher heating efficiency and effect are achieved.
Patent Information
- Application Number
- CN202421130866.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-22
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-05-22
AI Technical Summary
The L-shaped structure of traditional heaters leads to low utilization of space in the vehicle, and the majority of welded parts lead to large weight, high cost and high leakage risk.
A compact thick film heater is designed, adopting a rectangular structure, extending the circulation path of circulating water through the settings of the upper and lower partitions, increasing the heating area and time, and reducing welding parts, and combining parts onto the integrated die castings by non-welding.
It improves the use of the interior space, reduces the weight and cost of the heater, reduces the risk of water leakage, and improves the heating efficiency and effect.
Smart Images
Figure CN222637414U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of heaters, and in particular to a compact thick film heater. Background Art
[0002] In recent years, my country has been accelerating the transformation of automobile electrification, and the production and sales of new energy vehicles have continued to expand, driving the demand for thermal management systems. The batteries of electric vehicles need to be kept at a suitable operating temperature to ensure their performance and life. For example, when the temperature is low in winter, the performance and life of electric vehicle batteries will be affected because there is no engine to provide energy. The thermal management method has changed greatly. The thick film heater is a component in the thermal management system that heats the battery.
[0003] In the related art, the parts forming the water tank inside the traditional heater use a lot of stainless steel welding technology, and there are 14 welded parts. The traditional heater passes circulating water into the water tank and heats the circulating water to achieve heating of the battery. The circulating water is the engine coolant, specifically a mixture of ethylene glycol and water. The traditional heater is L-shaped as a whole, and its length × width × height dimensions are: 186.06 × 152.24 × 114.07mm. The space at the inner bend of the traditional heater is not fully utilized, resulting in low space utilization when the traditional heater is installed in the car. Utility Model Content
[0004] In order to improve the space utilization rate on the vehicle, the present application provides a compact thick film heater.
[0005] A compact thick film heater provided in this application adopts the following technical solution:
[0006] A compact thick film heater comprises a heater body, the heater body is arranged in a rectangular shape, the heater body comprises an upper cover plate, a middle frame and a lower cover plate, the upper cover plate and the lower cover plate are respectively fixedly connected to the upper and lower sides of the middle frame;
[0007] A first partition is fixedly connected inside the middle frame, the first partition divides the inside of the middle frame into an upper chamber and a lower chamber, a second partition is fixedly connected to the middle of the top surface of the upper first partition, the second partition divides the upper chamber into a right chamber and a left chamber, the right chamber is connected to the lower chamber, and the space inside the right chamber and the lower chamber is a water tank; an inlet pipe, an outlet pipe and a connector are connected to one end of the middle frame, the inlet pipe and the outlet pipe extend into the lower chamber and communicate with the lower chamber, and the connector is located between the inlet pipe and the outlet pipe;
[0008] A lower thick film plate is fixedly arranged at the opening in the lower chamber, an upper thick film plate is fixedly arranged at the opening in the right chamber, and a circuit board is fixedly arranged in the left chamber. The circuit board is electrically connected to the upper thick film plate, the lower thick film plate and the connector.
[0009] By adopting the above technical solution, when the heater of the present application is used, the heater is installed in the car, and circulating water is introduced from the water inlet pipe. The circulating water circulates between the lower chamber and the upper chamber, and then is discharged from the water outlet pipe to participate in the circulation. During the circulation process, the circulating water is connected and energized through the connector, and then the upper thick film plate and the lower thick film plate are heated through the circuit board electrical signal conversion, thereby realizing the heating of the circulating water in the upper chamber and the lower chamber to provide heat for the battery. The heater in the present application is arranged in a rectangular shape as a whole, which helps to save installation space and improve the space utilization rate on the vehicle compared to the heater arranged in an L shape as a whole, while meeting the requirements of normal use.
[0010] Optionally, a plurality of lower partition plates are arranged in parallel in the lower chamber, and the two lower partition plates located on the outermost edges are lower side partition plates, and both ends of the lower side partition plates are fixedly connected to the inner wall of the lower chamber; a lower water inlet channel and a lower water outlet channel are formed between the two lower side partition plates and the inner wall of the lower chamber, respectively, and the lower water inlet channel and the lower water outlet channel are connected to the water inlet pipe and the water outlet pipe, respectively;
[0011] The lower partition plate located in the middle is a lower middle partition plate, one end of which is fixedly connected to the inner wall of the lower chamber, and the other end of which is spaced from the inner wall of the lower chamber to form a connecting channel; the lower middle partition plate divides the space between the two lower side partition plates into a plurality of lower water guide channels;
[0012] The lower water inlet channel, the lower water outlet channel and the lower water guide channel are all provided with water holes at one end away from the connecting channel, and the water holes communicate with the upper chamber and the lower chamber;
[0013] A plurality of upper partition plates are arranged in parallel in the upper chamber, and the upper partition plates are arranged correspondingly to the lower partition plates; the two upper partition plates located on the edge are upper side partition plates, and one end of the upper side partition plates close to the water through hole is fixedly connected to the inner wall of the right chamber; the two upper side partition plates respectively form an upper water inlet channel and an upper water outlet channel with the inner wall of the lower chamber;
[0014] The upper partition plate located in the middle is the upper middle partition plate, both ends of which are fixedly connected to the inner wall of the right chamber, and the upper middle partition plate divides the space between the two upper side partition plates into multiple upper water guide channels.
[0015] By adopting the above technical solution, the flow process of circulating water in the heater is as follows: the circulating water enters the lower water inlet channel from the water inlet pipe, then enters the corresponding upper water inlet channel through the first water through hole, and then enters one of the upper water guide channels, and then enters one of the lower water guide channels through the corresponding water through hole, and then enters another lower water guide channel through the connecting channel, passes through the corresponding water through hole and then enters another upper water guide channel, and then enters the upper water outlet channel, and enters the lower water outlet channel through the corresponding water through hole, and finally is discharged from the water outlet pipe.
[0016] In this process, through the setting of the upper partition plate and the lower partition plate, the circulating water has a longer flow path in the upper chamber and the lower chamber, thereby increasing the time and area of the circulating water heated by the upper thick film plate and the lower thick film plate, which helps to improve the heating efficiency and effect.
[0017] Optionally, an upper thick film plate sealing rubber ring is fixedly connected to the bottom of the upper thick film plate, and a lower thick film plate sealing rubber ring is fixedly connected to the top of the lower thick film plate.
[0018] The adoption of the above technical solution helps to improve the sealing performance and reduce the occurrence of water leakage.
[0019] Optionally, the upper thick film plate is fixed to the top surface of the upper partition plate by screws, and the lower thick film plate is fixed to the bottom surface of the lower partition plate by screws.
[0020] By adopting the above technical solution, the structure is simple and easy to install.
[0021] Optionally, a first annular groove is opened at the side of the top of the middle frame, an upper cover sealing rubber ring is formed in the first annular groove by dispensing, and the top surface of the upper cover sealing rubber ring is fixedly connected to the bottom of the upper cover plate;
[0022] A second annular groove is opened at the side of the bottom of the middle frame, and a lower cover sealing rubber ring is formed in the second annular groove by dispensing, and the bottom surface of the lower cover sealing rubber ring is fixedly connected to the top of the lower cover plate.
[0023] The adoption of the above technical solution helps to improve the sealing performance and reduce the occurrence of water leakage.
[0024] Optionally, a first stainless steel ring is welded at the bottom of the upper thick film plate, a third annular groove is provided in the middle frame and on the outer side of the upper partition plate, a sealing rubber ring of the upper thick film plate is formed in the third annular groove by dispensing glue, and the first stainless steel ring is inserted into the third annular groove and fixedly connected to the sealing rubber ring of the upper thick film plate;
[0025] A second stainless steel ring is welded to the top of the lower thick film plate, and a fourth annular groove is provided in the middle frame and on the outer side of the lower partition plate. A sealing rubber ring of the lower thick film plate is formed in the fourth annular groove by dispensing glue, and the second stainless steel ring is inserted into the fourth annular groove and fixedly connected to the sealing rubber ring of the lower thick film plate. The remaining parts of the thick film heater are merged into the integral die-cast middle frame by a non-welding method.
[0026] By adopting the above technical solution, the traditional heater has a long weld and high welding quality requirements, resulting in a large overall weight, high cost, and easy water tank leakage. In this application, only four parts need to be welded, and the remaining parts are combined into an integrated die casting. The manufacturing cost of parts and welding costs are reduced, the risk of leakage is reduced, and it helps to reduce the overall weight of the heater.
[0027] Optionally, mounting side ears are fixedly connected to both sides of the middle frame.
[0028] By adopting the above technical solution, it is convenient to install the heater in the car.
[0029] In summary, the present application includes at least one of the following beneficial technical effects:
[0030] 1. The heater in this application is designed in a rectangular shape as a whole, under the premise of meeting normal use. Compared with the heater designed in an L-shape as a whole, it helps to save installation space and improve the space utilization rate on the vehicle;
[0031] 2. In this application, only four parts need to be welded, and the remaining parts are combined into an integral die-casting, which reduces the cost of parts manufacturing and welding, reduces the risk of water leakage, and helps to reduce the overall weight of the heater;
[0032] 3. Through the setting of the upper partition plate and the lower partition plate, the circulating water has a longer flow path in the upper chamber and the lower chamber, thereby increasing the time and area of the circulating water being heated by the upper thick film plate and the lower thick film plate, which helps to improve the heating efficiency and effect. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] Figure 1 It is a schematic diagram of the overall structure of a traditional heater in the background technology.
[0034] Figure 2 This is a diagram showing the parts that need to be welded inside a traditional heater in the background technology.
[0035] Figure 3 It is a schematic diagram of the overall structure of a compact thick film heater with the front side facing upwards according to an embodiment of the present application.
[0036] Figure 4It is a schematic diagram of the overall structure of a compact thick film heater with the reverse side facing upwards according to an embodiment of the present application.
[0037] Figure 5 It is an exploded view of a compact thick film heater according to an embodiment of the present application.
[0038] Figure 6 It is a structural schematic diagram used to show the right chamber and the left chamber in the embodiment of the present application.
[0039] Figure 7 It is a schematic diagram of the structure used to display the lower chamber in the embodiment of the present application.
[0040] Figure 8 It is a schematic diagram of the structure of parts that need to be welded in the embodiment of the present application.
[0041] Description of reference numerals: 1, upper cover; 11, upper cover sealing rubber ring; 2, middle frame; 21, mounting side ears; 22, first partition; 221, second partition; 23, water inlet pipe; 24, water outlet pipe; 25, connector; 3, lower cover; 31, lower cover sealing rubber ring; 4, upper chamber; 41, right chamber; 42, left chamber; 43, upper side partition; 44, upper water inlet channel; 45, upper water outlet channel; 46, upper middle partition; 47 , upper water guide channel; 5, lower chamber; 51, lower side partition plate; 52, lower water inlet channel; 53, lower water outlet channel; 54, lower middle partition plate; 55, connecting channel; 56, lower water guide channel; 57, water hole; 6, lower thick film plate; 61, lower thick film plate sealing rubber ring; 62, second stainless steel ring; 7, upper thick film plate; 71, upper thick film plate sealing rubber ring; 72, first stainless steel ring; 8, circuit board; 9, traditional heater. DETAILED DESCRIPTION
[0042] The following is combined with Figure 3-8 This application is described in further detail.
[0043] The present application embodiment discloses a compact thick film heater. Figure 3-7 The compact thick film heater includes a compact thick film heater, including a heater body, which is rectangular, and its length×width×height dimensions are: 259.75×186×50mm. The heater body includes an upper cover plate 1, a middle frame 2 and a lower cover plate 3, and the upper cover plate 1 and the lower cover plate 3 are respectively fixedly connected to the upper and lower sides of the middle frame 2. The two sides of the middle frame 2 are fixedly connected with mounting side ears 21, which facilitates the installation of the heater in the vehicle.
[0044] A first partition 22 is fixedly connected inside the middle frame 2, and the first partition 22 divides the interior of the middle frame 2 into an upper chamber 4 and a lower chamber 5. A second partition 221 is fixedly connected to the middle of the top surface of the upper first partition 22, and the second partition 221 divides the upper chamber 4 into a right chamber 41 and a left chamber 42. The right chamber 41 is connected to the lower chamber 5, and the space inside the right chamber 41 and the lower chamber 5 is a water tank; one end of the middle frame 2 is connected to a water inlet pipe 23, a water outlet pipe 24 and a connector 25, and the water inlet pipe 23 and the water outlet pipe 24 extend into the lower chamber 5 and are connected to the lower chamber 5, and the connector 25 is located between the water inlet pipe 23 and the water outlet pipe 24.
[0045] A lower thick film plate 6 is fixedly installed at the opening in the lower chamber 5, an upper thick film plate 7 is fixedly installed at the opening in the right chamber 41, and a circuit board 8 is fixedly installed in the left chamber 42. The circuit board 8 is electrically connected to the upper thick film plate 7, the lower thick film plate 6 and the connector 25.
[0046] When the heater of the present application is used, the heater is installed in the vehicle, and circulating water is introduced from the water inlet pipe 23. The circulating water is the engine coolant, specifically a mixture of ethylene glycol and water. The circulating water circulates between the lower chamber 5 and the upper chamber 4, and then is discharged from the water outlet pipe 24 to participate in the circulation. During the circulation process, the circulating water is connected and energized through the connector 25, and then the upper thick film plate 7 and the lower thick film plate 6 are heated through the electrical signal conversion of the circuit board 8, thereby realizing the heating of the circulating water in the upper chamber 4 and the lower chamber 5, and providing heat for the battery. The large planes of the upper thick film plate 7 and the lower thick film plate 6 can be welded with heat-conducting fins according to actual conditions, further increasing the heat exchange area and improving the heating effect. The heater in the present application is arranged in a rectangular shape as a whole, while meeting the requirements of normal use. Compared with the heater arranged in an L-shape as a whole, it helps to save about 25% of the installation space and improve the space utilization rate on the vehicle.
[0047] Reference Figure 7 A plurality of lower partition plates are arranged in parallel in the lower chamber 5, and the two lower partition plates located at the outermost edges are lower side partition plates 51, both ends of which are fixedly connected to the inner wall of the lower chamber 5; a lower water inlet channel 52 and a lower water outlet channel 53 are formed between the two lower side partition plates 51 and the inner wall of the lower chamber 5, respectively, and the lower water inlet channel 52 and the lower water outlet channel 53 are connected to the water inlet pipe 23 and the water outlet pipe 24, respectively.
[0048] The lower partition plate in the middle is the lower middle partition plate 54, one end of which is fixedly connected to the inner wall of the lower chamber 5, and the other end of the lower middle partition plate 54 is separated from the inner wall of the lower chamber 5 to form a connecting channel 55; the lower middle partition plate divides the space between the two lower side partition plates 51 into a plurality of lower water guide channels 56, and there are two lower water guide channels 56 in the embodiment of the present application. The lower water inlet channel 52, the lower water outlet channel 53 and the end of the lower water guide channel 56 away from the connecting channel 55 are all provided with water holes 57, and the water holes 57 connect the upper chamber 4 with the lower chamber 5;
[0049] Reference Figure 6 , multiple upper partition plates are arranged in parallel in the upper chamber 4, and the upper partition plates are arranged correspondingly to the lower partition plates; the two upper partition plates located on the edge are upper side edge partition plates 43, and one end of the upper side edge partition plate 43 close to the water through hole 57 is fixedly connected to the inner wall of the right chamber 41; the two upper side edge partition plates 43 respectively form an upper water inlet channel 44 and an upper water outlet channel 45 with the inner wall of the lower chamber 5; the upper partition plate located in the middle is an upper middle partition plate 46, and both ends of the upper middle partition plate 46 are fixedly connected to the inner wall of the right chamber 41, and the upper middle partition plate 46 divides the space between the two upper side edge partition plates 43 into multiple upper water guide channels 47. In the embodiment of the present application, there are two upper water guide channels 47.
[0050] The circulating water flows through the heater as follows: the circulating water enters the lower water inlet channel 52 from the water inlet pipe 23, then enters the corresponding upper water inlet channel 44 through the first water through hole 57, and then enters one of the upper water guide channels 47, and then enters one of the lower water guide channels 56 through the corresponding water through hole 57, and then enters another lower water guide channel 56 through the connecting channel 55, passes through the corresponding water through hole 57 and then enters another upper water guide channel 47, and then enters the upper water outlet channel 45, and enters the lower water outlet channel 53 through the corresponding water through hole 57, and finally is discharged from the water outlet pipe 24.
[0051] In this process, through the setting of the upper partition plate and the lower partition plate, the circulating water has a longer flow path in the upper chamber 4 and the lower chamber 5, thereby increasing the time and area of the circulating water being heated by the upper thick film plate 7 and the lower thick film plate 6, which helps to improve the heating efficiency and effect.
[0052] Reference Figure 5 and Figure 8A first stainless steel ring 72 is welded to the bottom of the upper thick film plate 7, a third annular groove is provided in the middle frame 2 and located on the outer side of the upper partition plate, and an upper thick film plate sealing rubber ring 71 is formed in the third annular groove by dispensing glue, and the first stainless steel ring 72 is inserted into the third annular groove and fixedly connected to the upper thick film plate sealing rubber ring 71; a second stainless steel ring 62 is welded to the top of the lower thick film plate 6, a fourth annular groove is provided in the middle frame 2 and located on the outer side of the lower partition plate, and a lower thick film plate sealing rubber ring 61 is formed in the fourth annular groove by dispensing glue, and the second stainless steel ring 62 is inserted into the fourth annular groove and fixedly connected to the lower thick film plate sealing rubber ring 61, and the remaining parts of the thick film heater are merged into the integral die-cast middle frame 2 by non-welding means.
[0053] Due to the long weld seams and high welding quality requirements of traditional heaters, the overall weight of the heater is large, the cost is high, and the water tank is prone to leaks. In this application, only four parts need to be welded, and the remaining parts are combined into an integrated die-casting. This reduces the cost of parts manufacturing and welding, reduces the risk of leaks, and helps reduce the overall weight of the heater.
[0054] Reference Figure 5 The upper thick film plate 7 is fixed to the top surface of the upper partition plate by screws, and the lower thick film plate 6 is fixed to the bottom surface of the lower partition plate by screws. The structure is simple and easy to install. A first annular groove is provided at the side of the top of the middle frame 2. An upper cover sealing rubber ring 11 is formed in the first annular groove by dispensing glue. The top surface of the upper cover sealing rubber ring 11 is fixedly connected to the bottom of the upper cover plate 1; a second annular groove is provided at the side of the bottom of the middle frame 2. A lower cover sealing rubber ring 31 is formed in the second annular groove by dispensing glue. The bottom surface of the lower cover sealing rubber ring 31 is fixedly connected to the top of the lower cover plate 3, which helps to further improve the sealing performance and reduce the occurrence of water leakage.
[0055] The implementation principle of a compact thick film heater in an embodiment of the present application is as follows: circulating water enters the lower water inlet channel 52 from the water inlet pipe 23, then enters the corresponding upper water inlet channel 44 through the first water through hole 57, and then enters one of the upper water guide channels 47, and then enters one of the lower water guide channels 56 through the corresponding water through hole 57, and then enters another lower water guide channel 56 through the connecting channel 55, passes through the corresponding water through hole 57 and then enters another upper water guide channel 47, and then enters the upper water outlet channel 45, and enters the lower water outlet channel 53 through the corresponding water through hole 57, and finally is discharged from the water outlet pipe 24.
[0056] In this process, the upper partition plate and the lower partition plate are arranged so that the circulating water has a longer flow path in the upper chamber 4 and the lower chamber 5, thereby increasing the time and area of the circulating water heated by the upper thick film plate 7 and the lower thick film plate 6, which helps to improve the heating efficiency and effect. In addition, the heater body is arranged in a rectangular shape as a whole, which helps to save installation space and improve the space utilization rate on the vehicle compared to the heater arranged in an L shape as a whole.
[0057] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A compact thick film heater, characterized in that: The heater body comprises a heater body, which is arranged in a rectangular shape, and comprises an upper cover plate (1), a middle frame (2) and a lower cover plate (3), wherein the upper cover plate (1) and the lower cover plate (3) are respectively fixedly connected to the upper and lower sides of the middle frame (2); A first partition (22) is fixedly connected inside the middle frame (2), and the first partition (22) divides the interior of the middle frame (2) into an upper chamber (4) and a lower chamber (5). A second partition (221) is fixedly connected to the middle of the top surface of the first partition (22), and the second partition (221) divides the upper chamber (4) into a right chamber (41) and a left chamber (42). The right chamber (41) is connected to the lower chamber (5), and the space inside the right chamber (41) and the lower chamber (5) is a water tank; one end of the middle frame (2) is connected to a water inlet pipe (23), a water outlet pipe (24) and a connector (25), and the water inlet pipe (23) and the water outlet pipe (24) extend into the lower chamber (5) and are connected to the lower chamber (5), and the connector (25) is located between the water inlet pipe (23) and the water outlet pipe (24); A lower thick film plate (6) is fixedly arranged at the opening in the lower chamber (5), an upper thick film plate (7) is fixedly arranged at the opening in the right chamber (41), and a circuit board (8) is fixedly arranged in the left chamber (42). The circuit board (8) is electrically connected to the upper thick film plate (7), the lower thick film plate (6) and the connector (25).
2. A compact thick film heater according to claim 1, characterized in that: A plurality of lower partition plates are arranged in parallel in the lower chamber (5), the two lower partition plates located at the outermost edges are lower side partition plates (51), both ends of the lower side partition plates (51) are fixedly connected to the inner wall of the lower chamber (5); a lower water inlet channel (52) and a lower water outlet channel (53) are formed between the two lower side partition plates (51) and the inner wall of the lower chamber (5), respectively, and the lower water inlet channel (52) and the lower water outlet channel (53) are connected to the water inlet pipe (23) and the water outlet pipe (24) respectively; The lower partition plate located in the middle is a lower middle partition plate (54); one end of the lower middle partition plate (54) is fixedly connected to the inner wall of the lower chamber (5); the other end of the lower middle partition plate (54) is spaced from the inner wall of the lower chamber (5) to form a connecting channel (55); the lower middle partition plate divides the space between the two lower side partition plates (51) into a plurality of lower water guide channels (56); The lower water inlet channel (52), the lower water outlet channel (53) and the lower water guide channel (56) are all provided with a water hole (57) at one end away from the connecting channel (55), and the water hole (57) communicates with the upper chamber (4) and the lower chamber (5); A plurality of upper partition plates are arranged in parallel in the upper chamber (4), and the upper partition plates are arranged correspondingly to the lower partition plates; the two upper partition plates located at the edge are upper side partition plates (43), and one end of the upper side partition plates (43) close to the water through hole (57) is fixedly connected to the inner wall of the right chamber (41); an upper water inlet channel (44) and an upper water outlet channel (45) are formed between the two upper side partition plates (43) and the inner wall of the lower chamber (5); The upper partition plate located in the middle is an upper middle partition plate (46), both ends of which are fixedly connected to the inner wall of the right chamber (41), and the upper middle partition plate (46) divides the space between the two upper side partition plates (43) into a plurality of upper water guide channels (47).
3. A compact thick film heater according to claim 1 or 2, characterized in that: An upper thick film plate sealing rubber ring (71) is fixedly connected to the bottom of the upper thick film plate (7), and a lower thick film plate sealing rubber ring (61) is fixedly connected to the top of the lower thick film plate (6).
4. A compact thick film heater according to claim 2, characterized in that: The upper thick film plate (7) is fixed to the top surface of the upper partition plate by means of screws, and the lower thick film plate (6) is fixed to the bottom surface of the lower partition plate by means of screws.
5. A compact thick film heater according to claim 1, 2 or 4, characterized in that: A first annular groove is provided at the side edge of the top of the middle frame (2), an upper cover sealing rubber ring (11) is formed in the first annular groove by dispensing, and the top surface of the upper cover sealing rubber ring (11) is fixedly connected to the bottom of the upper cover plate (1); A second annular groove is provided at the side edge of the bottom of the middle frame (2), a lower cover sealing rubber ring (31) is formed in the second annular groove by dispensing glue, and the bottom surface of the lower cover sealing rubber ring (31) is fixedly connected to the top of the lower cover plate (3).
6. A compact thick film heater according to claim 3, characterized in that: A first stainless steel ring (72) is welded to the bottom of the upper thick film plate (7), a third annular groove is provided in the middle frame (2) and located on the outer side of the upper partition plate, an upper thick film plate sealing rubber ring (71) is formed in the third annular groove by dispensing glue, and the first stainless steel ring (72) is inserted into the third annular groove and fixedly connected to the upper thick film plate sealing rubber ring (71); A second stainless steel ring (62) is welded to the top of the lower thick film plate (6), a fourth annular groove is provided in the middle frame (2) and on the outer side of the lower partition plate, a lower thick film plate sealing rubber ring (61) is formed in the fourth annular groove by dispensing glue, the second stainless steel ring (62) is inserted into the fourth annular groove and fixedly connected to the lower thick film plate sealing rubber ring (61), and the remaining parts of the thick film heater are combined with the integral die-cast middle frame (2) by non-welding means.
7. A compact thick film heater according to claim 1, 2, 4 or 6, characterized in that: Mounting side ears (21) are fixedly connected to both sides of the middle frame (2).