Dry burning protection device of PTC heater

Abstract

A dry burning protection device of a PTC heater comprises a PCBA and an NTC temperature sensor pasted on the PCBA, a heating core body is connected with the PCBA through a positive electrode plate, the positive electrode plate is welded on the PCBA, and the NTC temperature sensor is located in a preset range near a welding hole of the positive electrode plate of the heating core body and the PCBA. According to the PTC, the NTC temperature sensor is integrated on the PCBA, the design is optimized, the space is saved, and an effective ventilation area of a product is prevented from being locally shielded; according to the PTC, a temperature sensor does not need to be installed manually, production takt is accelerated, and labor cost is saved.

Description

Technical Field

[0001] The utility model relates to the technical field of temperature protection of electric heating bodies, in particular to a dry-burning protection device for a PTC heater. Background Art

[0002] With the popularization of new energy vehicles, controlled PTC heaters are vigorously developed. At the same time, the heating safety of PTC heaters cannot be ignored. Therefore, it is necessary to measure the temperature of the heating core of the PTC heater in real time and accurately so that the processor can judge whether the heating core is abnormal through the temperature of the heating core. The existing technologies include: 1. Use screws to fix the temperature sensor on the side of the heating core to collect the core temperature; 2. Punch holes in the heat dissipation strip, install the temperature sensor and fix it with screws to collect the product fin temperature. Both methods require manual screwing operations, which not only slows down the production cycle, but also has high labor costs. At the same time, the temperature sensor will occupy part of the ventilation area space. Utility Model Content

[0003] In view of the technical defects and technical drawbacks in the prior art, the embodiments of the present utility model provide a PTC heater temperature acquisition device and a PTC heater that overcome the above problems or at least partially solve the above problems. The specific scheme is as follows:

[0004] A dry burning protection device for a PTC heater comprises a PCBA and an NTC temperature sensor mounted on the PCBA, wherein a heating core is connected to the PCBA via a positive electrode sheet, the positive electrode sheet is welded on the PCBA, and the NTC temperature sensor is located within a preset range near a welding hole between the positive electrode sheet of the heating core and the PCBA.

[0005] Furthermore, the NTC temperature sensor is a chip-type NTC temperature sensor, and the chip-type NTC temperature sensor is welded and integrated on the PCBA when the circuit board corresponding to the PCBA is mounted.

[0006] Furthermore, the NTC temperature sensor is 3-5 mm away from the welding hole between the positive electrode sheet of the heating core and the PCBA.

[0007] Furthermore, the device also includes a processor for calculating the temperature of the heating core according to the power P of the heating core, the thermal resistance R of the NTC temperature sensor, and the PCBA temperature measured by the NTC temperature sensor, and the processor is electrically connected to the NTC temperature sensor.

[0008] Furthermore, the processor pre-stores the power P of the heating core, the thermal resistance R of the NTC temperature sensor, and a heating core temperature threshold for determining whether the temperature of the heating core is abnormal.

[0009] Furthermore, the device also includes an alarm for giving an alarm when the temperature of the heating core is abnormal, and the alarm is electrically connected to the processor.

[0010] Further, the NTC temperature sensor is electrically connected to the signal input port of the processor to transmit the measured PCBA temperature to the processor.

[0011] Furthermore, the processor is an MCU microprocessor.

[0012] Furthermore, the device also includes a relay for cutting off the power supply of the heating core, the relay is connected in series to the power supply line of the heating core, and the control end of the relay is electrically connected to the processor to receive a control signal from the processor.

[0013] The utility model has the following beneficial effects:

[0014] 1. The utility model PTC integrates the NTC temperature sensor on the PCBA, optimizes the design, saves space, and avoids partial obstruction of the effective ventilation area of ​​the product;

[0015] 2. This design is based on the thermal resistance formula R = (T2-T1) / P. Through the known core power, NTC temperature sensor thermal resistance R and NTC temperature sensor detection temperature, the core temperature can be indirectly reflected, temperature monitoring can be achieved, and a protective effect can be played;

[0016] 3. PTC does not require manual installation of temperature sensors, which speeds up production and saves labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the structure of a PTC heater temperature acquisition device provided in an embodiment of the utility model.

[0019] In the figure: 1- positive electrode sheet, 2- NTC temperature sensor, 3- heating core. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the utility model, not all embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0022] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present utility model, unless otherwise specified, "multiple" and "several" mean two or more.

[0023] like Figure 1 As shown, as the first embodiment of the utility model, a PCBA and an NTC temperature sensor 2 mounted on the PCBA are provided, the heating core 3 is connected to the PCBA through the positive electrode sheet 1, the positive electrode sheet 1 is welded to the PCBA, the NTC temperature sensor 2 is located within a preset range near the welding hole between the positive electrode sheet 1 of the heating core 3 and the PCBA, and the NTC temperature sensor 2 is not in direct contact with the heating core 3 and its positive electrode sheet 1.

[0024] At present, the temperature acquisition of PTC heaters includes: 1. Fixing the NTC temperature sensor 2 on the heating core 3 by screws, 2. Punching holes in the heat sink and installing the NTC temperature sensor 2 on the heat sink; both methods require manual screwing operations, which not only slows down the production cycle and has high labor costs, but also installs the NTC inside the heat sink. In this installation method, the sensor will occupy a part of the ventilation area of ​​the heat sink. The utility model integrates the NTC on the PCBA instead of the heating core 3, thereby saving the design space of the core part and avoiding the sensor from partially blocking the ventilation area of ​​the heating core 3, and reducing the assembly and screwing processes in the production process.

[0025] The utility model provides a PTC heater temperature acquisition device, which utilizes the thermal resistance formula R=(T2-T1) / P. According to the transformation of the formula, T2=R*P+T1 can be obtained, wherein the power P of the heating core 3 is known, the thermal resistance R of the NTC temperature sensor 2 is known, and the core temperature T2 can be known by the temperature value T1 detected by the NTC temperature sensor 2.

[0026] Among them, the NTC temperature sensor 2 of the utility model can be one or more, corresponding to the case of one or more positive electrode sheets 1, and the measurement accuracy can be increased by measuring multiple NTC temperature sensors 2 at the same time. For example, the measurement values ​​obtained by multiple NTC temperature sensors 2 are averaged, or the maximum measurement value thereof is used as the standard. This utility model does not make specific limitations on this; Figure 1 As shown, an embodiment of the present invention provides a case of three positive electrode sheets 1. In specific applications, corresponding adjustments can be made according to the specific number of positive electrode sheets 1. For example, when the heating core 3 is connected to the PCBA through only one positive electrode sheet 1, there is only one corresponding NTC temperature sensor 2.

[0027] The NTC temperature sensor 2 is a surface mount NTC temperature sensor 2, and the surface mount NTC temperature sensor 2 is soldered on the PCBA when the circuit board corresponding to the PCBA is surface mounted.

[0028] Among them, the NTC temperature sensor 2 is 3-5mm away from the welding hole of the positive electrode sheet 1 of the heating core 3 and the PCBA. It has been verified that when the NTC temperature sensor 2 is 3-5mm away from the welding hole, the core temperature error calculated based on the thermal resistance formula R=(T2-T1) / P is the smallest.

[0029] As a second embodiment of the utility model, the device further includes a processor for calculating the temperature of the heating core 3 through the power P of the heating core 3, the thermal resistance R of the NTC temperature sensor 2, and the PCBA temperature measured by the NTC temperature sensor 2, and the NTC temperature sensor 2 is electrically connected to the signal input port of the processor to transmit the measured PCBA temperature to the processor.

[0030] The processor pre-stores the power P of the heating core 3 , the thermal resistance R of the NTC temperature sensor 2 , and a temperature threshold of the heating core 3 for determining whether the temperature of the heating core 3 is abnormal.

[0031] The processor may be an MCU microprocessor, FPGA, CPU, single-chip microcomputer, etc.

[0032] In the above embodiment, the processor obtains the PCBA temperature through the NTC temperature sensor 2, combined with the thermal resistance formula R=(T2-T1) / P, to calculate the temperature of the heating core 3, and then based on the temperature threshold of the heating core 3, it can be determined whether the temperature of the heating core 3 is abnormal.

[0033] Among them, the device also includes an alarm for alarming when the temperature of the heating core 3 is abnormal and a relay for cutting off the power supply of the heating core 3. The alarm and the relay are both electrically connected to the processor, and the relay is connected in series to the power supply line of the heating core 3. The control end of the relay is electrically connected to the processor to receive the control signal of the processor.

[0034] In the above embodiment, the processor, alarm and relay can be integrated on the PCBA or set in the background. The processor is electrically connected to the alarm through a wireless communication module. When the temperature of the heating core 3 is abnormal, the alarm can be used to give a timely alarm, and the power supply of the heating core 3 can be cut off in time through the relay. The alarm can be an existing sound alarm or an alarm light.

[0035] It should be noted that the scheme for which protection is requested in the present utility model is about the selection and connection relationship of various hardware devices, and when a person skilled in the art learns about the hardware scheme of the present application, he can obtain the corresponding upper-level program or calculation formula without any objection, so the scheme for which protection is requested in the present application does not involve program improvement.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dry burning protection device for a PTC heater, characterized in that: The invention comprises a PCBA and an NTC temperature sensor mounted on the PCBA. The heating core is connected to the PCBA through a positive electrode sheet, the positive electrode sheet is welded on the PCBA, and the NTC temperature sensor is located within a preset range near a welding hole between the positive electrode sheet of the heating core and the PCBA.

2. The dry burning protection device of the PTC heater according to claim 1, characterized in that: The NTC temperature sensor is a patch type NTC temperature sensor.

3. The dry burning protection device of the PTC heater according to claim 1, characterized in that: The NTC temperature sensor is 3-5 mm away from the welding hole between the positive electrode sheet of the heating core and the PCBA.

4. The dry burning protection device of the PTC heater according to claim 1, characterized in that: The device further comprises a processor for calculating the temperature of the heating core according to the power P of the heating core, the thermal resistance R of the NTC temperature sensor and the PCBA temperature measured by the NTC temperature sensor, wherein the processor is electrically connected to the NTC temperature sensor.

5. The dry burning protection device of the PTC heater according to claim 4, characterized in that: The processor pre-stores the power P of the heating core, the thermal resistance R of the NTC temperature sensor, and a heating core temperature threshold for determining whether the temperature of the heating core is abnormal.

6. The dry burning protection device of the PTC heater according to claim 4, characterized in that: The device also includes an alarm for giving an alarm when the temperature of the heating core is abnormal, and the alarm is electrically connected to the processor.

7. The dry burning protection device of the PTC heater according to claim 4, characterized in that: The NTC temperature sensor is electrically connected to the signal input port of the processor to transmit the measured PCBA temperature to the processor.

8. The dry burning protection device of the PTC heater according to claim 4, characterized in that: The processor is a MCU microprocessor.

9. The dry burning protection device of the PTC heater according to claim 4, characterized in that: The device also includes a relay for cutting off the power supply of the heating core, the relay is connected in series to the power supply line of the heating core, and the control end of the relay is electrically connected to the processor to receive a control signal from the processor.

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