Temperature and pressure sensor

Abstract

A temperature and pressure sensor comprises a shell, and a plug assembly is arranged on the upper portion of the shell. A circuit board, a ceramic capacitor, a resistor support and a thermistor are sequentially arranged in the shell from top to bottom, a plurality of contact pins are installed in the plug assembly, the lower ends of the contact pins are connected with the circuit board through tin soldering, and the circuit board is connected with the ceramic capacitor through tin soldering; the thermistor and the resistor support are connected in a resistance welding mode. The upper end of the resistor support is electrically connected with the ceramic capacitor. Wherein the temperature function and the pressure function are integrated, two electrodes are arranged at the bottom of the ceramic capacitor and elastically connected with contacts of the resistor support to form electrical contact, two pins are additionally designed on the front face of the ceramic, and the pins are communicated with the two electrodes at the bottom of the ceramic respectively, so that the function of leading out temperature and resistance signals is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat pump equipment, more specifically to a temperature and pressure sensor. Background Art

[0002] With the popularization of heat pump systems, especially the application of electronic expansion valves, real-time and accurate monitoring of pressure and temperature is required. In the past, pressure sensors were used to collect pressure signals, and temperature sensors were used to collect temperature signals. Due to the split collection method and the high-pressure flow rate of the medium, the pressure and temperature collection are not synchronized, affecting the precise control of the system. Therefore, the integrated pressure and temperature combination structure sensor (temperature and pressure sensor) has also become a new application trend of heat pump systems. In addition, due to the presence of internal metal debris in the manufacturing of metal parts such as air-conditioning metal pipes, the system medium will be mixed with such metal debris impurities, resulting in short-circuiting of the thermistor pins of the temperature and pressure sensor and failure of the temperature measurement function.

[0003] Currently, the signal acquisition mainly adopts the split solution of pressure sensor and temperature sensor. The pressure signal and temperature signal are not synchronized. The system needs to arrange two installation spaces, which increases the risk of medium leakage. Although there are integrated solutions of pressure and temperature functions on the market, the resistor pins are exposed. Metal debris in the pipeline system can easily cause the resistor pins to short-circuit, resulting in failure of temperature signal acquisition. Utility Model Content

[0004] One advantage of the utility model is that it provides a temperature and pressure sensor in which the temperature function and the pressure function are integrated into one, wherein two electrodes are provided at the bottom of the ceramic capacitor, which are elastically connected to the contacts of the resistor bracket to form electrical contact, and two pins are designed on the front side of the ceramic, which are respectively connected to the two electrodes at the bottom of the ceramic, thereby realizing the function of drawing out temperature and resistance signals.

[0005] One advantage of the utility model is that it provides a temperature and pressure sensor, in which all devices are installed inside the same housing, thereby improving the degree of integration and effectively reducing the possibility of damage.

[0006] One advantage of the utility model is that it provides a temperature and pressure sensor, wherein the notch at the bottom of the sheath is set to 1×0.5 mm, thereby reducing the amount of metal debris entering.

[0007] One advantage of the utility model is that it provides a temperature and pressure sensor, in which convex points are arranged on both sides of the middle part of the injection molding baffle, and the outermost distance between the two convex points is equal to the distance between the two resistor pins of the thermistor in a parallel state. When the thermistor is installed on the resistor bracket, the two convex points can spread the resistor pins of the thermistor and ensure that they are in a parallel state, making it easier to weld.

[0008] In order to achieve at least one of the above advantages of the utility model, the utility model provides a temperature and pressure sensor, including a housing, wherein a plug assembly is disposed on the upper portion of the housing;

[0009] A circuit board, a ceramic capacitor, a resistor bracket and a thermistor are arranged in sequence inside the housing from top to bottom. A plurality of pins are installed inside the plug assembly. The lower ends of the pins are connected to the circuit board by soldering, and the circuit board is connected to the ceramic capacitor by soldering.

[0010] The thermistor and the resistor bracket are connected by resistance welding, and the upper end of the resistor bracket is electrically connected to the ceramic capacitor.

[0011] According to an embodiment of the utility model, a resistor sheath is further connected to the lower end of the shell, and the resistor sheath is a cylindrical structure with upper and lower openings, and the resistor sheath is located outside the resistor bracket and the thermistor.

[0012] According to an embodiment of the utility model, a notch is provided at the lower opening of the resistor sheath, the width of the notch is 0.5 mm, and the height of the notch is 1.0 mm.

[0013] According to an embodiment of the utility model, it also includes a base, and an injection-molded baffle is installed in the middle of the lower end of the base;

[0014] The upper part and the lower part of the ceramic capacitor are respectively provided with ceramic pins and metal electrodes;

[0015] The resistor bracket is a stainless steel elastic structure with a contact on the top. The contact passes through the base and is mechanically connected to the metal electrode. The injection molded baffle is located between the two resistor brackets. The injection molded baffle is connected to the resistor bracket by resistance welding to prevent foreign matter short-circuit failure of the resistor bracket.

[0016] According to an embodiment of the present invention, the ceramic pins are connected to the circuit board by soldering.

[0017] According to an embodiment of the utility model, an inner sealing ring is arranged between the housing and the ceramic capacitor.

[0018] According to an embodiment of the utility model, an outer sealing ring is arranged outside the shell.

[0019] According to an embodiment of the utility model, a resistor pin is provided at the upper end of the thermistor, and the thermistor is connected to the resistor bracket through the resistor pin by resistance welding.

[0020] According to an embodiment of the utility model, convex points are arranged on both sides of the middle part of the injection molding baffle, and the distance between the outermost sides of the two convex points is equal to the distance between the two resistor pins of the thermistor in a parallel state. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the utility model;

[0022] Figure 2 It is a cross-sectional schematic diagram of the utility model;

[0023] Figure 3 This is a schematic diagram of the upper part of the ceramic capacitor of the utility model;

[0024] Figure 4 This is a schematic diagram of the resistor bracket of the utility model;

[0025] Figure 5 This is a schematic diagram of the lower part of the ceramic capacitor of the utility model;

[0026] In the attached figure: 1. plug assembly, 2. circuit board assembly, 3. ceramic capacitor, 4. inner sealing ring, 5. resistor bracket, 6. thermistor, 7. resistor sheath, 8. shell, 9. outer sealing ring, 10. pin, 11. resistor pin, 12. contact, 13. metal electrode, 14. ceramic pin, 15. baffle, 16. base, 17. injection molded baffle. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present invention more clear, the following will be combined with the appendix of the present invention. Figure 1 ~Attached Figure 5 , the utility model is described in more detail.

[0028] The following description is used to disclose the utility model so that those skilled in the art can implement the utility model. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the utility model defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the utility model.

[0029] Those skilled in the art should understand that, in the disclosure of the specification, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, which 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 orientation, be constructed and operated in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0030] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0031] The utility model provides a temperature and pressure sensor, including a shell, wherein a plug assembly is arranged on the upper part of the shell; a circuit board, a ceramic capacitor, a resistor bracket and a thermistor are arranged in sequence inside the shell from top to bottom, and a plurality of pins are installed inside the plug assembly, wherein the lower ends of the pins are connected to the circuit board by soldering, and the circuit board is connected to the ceramic capacitor by soldering; the thermistor and the resistor bracket are connected by resistance welding, and the upper end of the resistor bracket is electrically connected to the ceramic capacitor; a resistor sheath is also connected to the lower end of the shell, wherein the resistor sheath is a cylindrical structure with upper and lower openings, and the resistor sheath is located outside the resistor bracket and the thermistor; a notch is arranged at the lower end opening of the resistor sheath, wherein the width of the notch is 0.5 mm, and the height of the notch is 1.0 mm; according to an embodiment of the utility model, a base is also included, wherein the base An injection molding baffle is installed in the middle of the lower end; ceramic pins and metal electrodes are respectively arranged at the upper and lower parts of the ceramic capacitor; the resistor bracket is a stainless steel elastic structure, and a contact is arranged on the top thereof, and the contact is mechanically connected to the metal electrode through the base, and the injection molding baffle is located between the two resistor brackets, and the injection molding baffle is connected to the resistor bracket by resistance welding to prevent foreign matter short circuit failure of the resistor bracket; the ceramic pin is connected to the circuit board by soldering; an inner sealing ring is arranged between the shell and the ceramic capacitor; an outer sealing ring is arranged on the outside of the shell; a resistor pin is arranged at the upper end of the thermistor, and the thermistor is connected to the resistor bracket by resistance welding through the resistor pin; bumps are arranged on both sides of the middle part of the injection molding baffle, and the distance between the outermost sides of the two bumps is equal to the distance between the two resistor pins of the thermistor in a parallel state.

[0032] Embodiment 1 of the present utility model is as follows:

[0033] The sensor has two major functions, including a pressure performance path and a temperature function path.

[0034] The pressure performance path is: measuring medium → housing 8 → ceramic capacitor 3 → circuit board assembly 2 → plug assembly 1 → system controller, wherein the ceramic capacitor 3 will be converted into different capacitance values ​​according to the different medium pressures, and the circuit board assembly 2 will convert the capacitance value into a standard voltage signal, which is transmitted to the system controller through the plug assembly 1; the circuit board assembly 2 is respectively connected to the ceramic capacitor 3 and the plug assembly 1 by soldering; there is an inner sealing ring 4 between the housing 8 and the ceramic capacitor 3, which is mainly used to prevent the medium from directly contacting the circuit board assembly 2 and corroding and damaging the circuit components;

[0035] Among them, the temperature function path is: measuring medium → housing 8 → thermistor 6 → ceramic capacitor 3 → circuit board assembly 2 → plug assembly 1 → system controller; the thermistor 6 adopts a negative temperature coefficient resistor. When the temperature is low, the number of carriers (electrons and holes) of metal oxide materials such as manganese, cobalt, nickel and copper is small, so its resistance value is relatively high; as the temperature increases, the number of carriers increases, so the resistance value decreases.

[0036] A resistor sheath 7 is designed on the outside of the thermistor 6 to protect the thermistor 6 from being impacted by large pressure and directly hit by external foreign objects. The resistor pin 11 of the thermistor 6 is connected to the resistor bracket 5 by resistance welding. The resistor bracket 5 is a stainless steel elastic structure with a contact 12 on the top. The contact 12 is gold-plated. The contact 12 is in contact with two metal electrodes 13 of the ceramic capacitor 3. The ceramic capacitor 3 mainly has a mechanical connection function. The two exposed metal electrodes 13 at the bottom are connected to the two ceramic pins 14 on the top of the ceramic respectively. The ceramic pin 14 is then connected to the circuit board assembly 2 by soldering. The circuit board also has a mechanical connection function. The other end is soldered to the plug assembly 1.

[0037] This solution mainly integrates the temperature function and the pressure function, wherein there are two metal electrodes 13 at the bottom of the ceramic capacitor 3, and the metal electrode 13 is an open-hole electrode, which is elastically connected to the gold-plated contact 12 of the resistor bracket 5 to form an electrical contact. Two pins are designed on the front of the ceramic capacitor 3, and the pins are respectively connected to the two metal electrodes 13 at the bottom of the ceramic capacitor 3, thereby realizing the function of drawing out the temperature resistance signal.

[0038] Thermistor 6 anti-short circuit design description:

[0039] Since there are metal debris in the system application pipeline, these metal foreign objects may enter the sensor and cause the thermistor 6 to short-circuit. To prevent this application failure, the product has been optimized and improved:

[0040] Four notches are arranged in a cross-shaped manner at the bottom of the resistor sheath 7, and the notches are arranged to have a size of 1×0.5 mm to reduce the amount of metal debris entering.

[0041] An injection-molded baffle is provided to separate the two resistor brackets and connect them by resistance welding, which can effectively avoid short circuit between the two resistor brackets caused by foreign matter.

[0042] At the same time, convex points are set on both sides of the middle part of the injection molding baffle. The outermost distance between the two convex points is equal to the distance between the two resistor pins of the thermistor in a parallel state. When the thermistor is installed on the resistor bracket, the two convex points can prop up the resistor pins of the thermistor and ensure that they are in a parallel state, making welding easier.

[0043] Compared with the split type application, the device provided by the utility model can reduce one installation space and reduce the risk of system leakage;

[0044] And it has a resistance anti-short circuit design to avoid metal debris in the system entering the sensor and causing a short circuit failure of the thermistor 6.

[0045] Another embodiment of the present invention is as follows:

[0046] A baffle is also provided at the bottom of the ceramic capacitor. The contact 12 of the resistor bracket 5 is designed with a contact protection ring, the area of ​​which is not less than the opening of the metal electrode 13 of the ceramic capacitor 3. The contact protection ring is made of HNBR dielectric-resistant material to prevent foreign matter short-circuit failure at the contact 12 end of the resistor bracket 5. At the same time, the exposed parts of the resistor bracket and thermistor except the contacts are coated with three-proof paint for protection to prevent short-circuit between the thermistor pins and the resistor bracket springs.

[0047] The exposed parts of the resistor bracket 5 and the thermistor 6 except the contact 12 of the resistor bracket 5 are coated with a conformal coating to prevent a short circuit between the resistor pin 11 of the thermistor 6 and the resistor bracket 5 .

[0048] The other structures are the same as those of the first embodiment and will not be described again.

[0049] It should be noted that the terms "first, second and third" in the present invention are only used for descriptive purposes and do not indicate any order. They cannot be understood as indicating or implying relative importance. These terms can be interpreted as names.

[0050] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The advantages of the present invention have been fully and effectively realized. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A temperature and pressure sensor, characterized in that: It comprises a housing, and a plug assembly is arranged on the upper part of the housing; A circuit board, a ceramic capacitor, a resistor bracket and a thermistor are arranged in sequence inside the housing from top to bottom. A plurality of pins are installed inside the plug assembly. The lower ends of the pins are connected to the circuit board by soldering, and the circuit board is connected to the ceramic capacitor by soldering. The thermistor and the resistor bracket are connected by resistance welding, and the upper end of the resistor bracket is electrically connected to the ceramic capacitor.

2. The temperature and pressure sensor according to claim 1, characterized in that: The lower end of the shell is also connected to a resistor sheath, which is a cylindrical structure with upper and lower openings. The resistor sheath is located outside the resistor bracket and the thermistor.

3. The temperature and pressure sensor according to claim 2, characterized in that: A notch is provided at the lower opening of the resistance sheath, the width of the notch is 0.5 mm, and the height of the notch is 1.0 mm.

4. The temperature and pressure sensor according to claim 1, characterized in that: It also includes a base, wherein an injection-molded baffle is installed in the middle of the lower end of the base; The upper part and the lower part of the ceramic capacitor are respectively provided with ceramic pins and metal electrodes; The resistor bracket is a stainless steel elastic structure with a contact on the top. The contact passes through the base and is mechanically connected to the metal electrode. The injection molded baffle is located between the two resistor brackets. The injection molded baffle is connected to the resistor bracket by resistance welding to prevent foreign matter short-circuit failure of the resistor bracket.

5. The temperature and pressure sensor according to claim 4, characterized in that: The ceramic pins are connected to the circuit board by soldering.

6. The temperature and pressure sensor according to claim 1, characterized in that: An inner sealing ring is arranged between the shell and the ceramic capacitor.

7. The temperature and pressure sensor according to claim 1, characterized in that: An outer sealing ring is arranged outside the shell.

8. The temperature and pressure sensor according to claim 4, characterized in that: A resistor pin is arranged at the upper end of the thermistor, and the thermistor is connected to the resistor bracket through the resistor pin by resistance welding.

9. The temperature and pressure sensor according to claim 8, characterized in that: Both sides of the middle part of the injection molding baffle are provided with convex points, and the distance between the outermost sides of the two convex points is equal to the distance between the two resistor pins of the thermistor in a parallel state.

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