A ceramic capacitive temperature and pressure sensor

Abstract

The application relates to the technical field of sensors, in particular to a ceramic capacitive temperature and pressure sensor which comprises a pressure port seat, a base, a ceramic capacitor, a temperature sensing assembly, an NTC adapter plate, an electric connector and a PFC circuit board; the pressure port seat and the base are connected through embedding and double sealing to ensure lossless pressure transmission; the base and the temperature sensing assembly are supported in layers through NTC struts to prevent deviation and short circuit; the NTC adapter plate realizes non-perforation signal transfer and protects the ceramic capacitor structure; the electric connector and the base are quickly connected through clamping, and the PFC circuit board is adapted to deviation and anti-interference through elastic flanging and flexible grounding arms. The sensor solves the problems of structure damage, signal distortion and low assembly efficiency in the prior art, is suitable for high-pressure, vibration and narrow-space working conditions, and has high temperature and pressure detection precision and high stability.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of sensors, and in particular to a ceramic capacitive temperature and pressure sensor. BACKGROUND

[0002] The core requirement of the ceramic capacitive temperature and pressure sensor is to realize accurate collection and reliable transmission of the "pressure-temperature" double signals, and the performance thereof depends on the cooperative work of three modules, i.e., a pressure sensing (ceramic capacitor), a temperature sensing (NTC component) and a signal processing (circuit board), and the connection relationship among the modules directly determines the precision, stability and service life of the sensor. The prior art has the following key defects, all of which are related to unreasonable connection relationship design.

[0003] 1. Ceramic capacitor structure damage and pressure transmission loss: in order to realize the connection of the NTC and the circuit board, a traditional scheme, such as the patent application with the publication number CN223077765U, discloses a temperature and pressure sensor for new refrigerants, which comprises a shell with a built-in pressure sensing component, the shell is externally connected with an electrical connector connected with the pressure sensing component, and the shell is internally provided with an NTC thermistor connected with the pressure sensing component; the pressure sensing component is a five-pin ceramic capacitor, two pins of the five-pin ceramic capacitor are temperature measuring pins penetrating the ceramic capacitor body to connect the NTC thermistor, and a pressure protection ring surrounding the temperature measuring pins is arranged between the pressure sensing component and the shell. The patent application uses a five-pin ceramic capacitor as the pressure sensing component, two pins for temperature measurement are designed in a straight-through structure, and a double-ring pressure protection ring is arranged to improve the pressure resistance of the temperature and pressure sensor. The scheme needs to open a penetrating hole on the ceramic capacitor (pressure sensing core, which depends on the complete ceramic base to ensure uniform stress), which damages the structural integrity of the ceramic capacitor, causes the stress distribution of the pressure sensing diaphragm to be unbalanced, and reduces the linearity of pressure detection; at the same time, the pressure channel is mostly designed to be curved or cooperates with other components in a gap, which is easy to cause pressure hysteresis or leakage, further reducing the detection accuracy.

[0004] 2. Temperature sensing component support failure and signal short circuit risk: the NTC temperature sensing pins lack targeted guiding support and are only fixed by simple insertion, which is easy to deviate and bend under vibration conditions, causing the position of the NTC thermistor to be misaligned and the temperature detection deviation to be enlarged; more seriously, the V-shaped connection part of the temperature sensing pins and the NTC has no isolation structure, and the two pins are easy to contact and short circuit, directly causing the temperature signal to be interrupted and the sensor to fail.

[0005] 3. Insufficient connection rigidity and anti-interference of PFC circuit board: the circuit board is mostly rigidly connected with the ceramic capacitor and the NTC component, and a small deviation during assembly is easy to cause the ceramic capacitor pins to be bent and the pin body to be in poor contact; at the same time, the grounding structure depends on wire welding, and the disconnection rate is high under vibration environment, the grounding resistance fluctuates greatly, and electromagnetic interference (such as frequency converter and motor noise) in industrial scenes will directly invade the signal circuit, causing the temperature and pressure detection error to be doubled.

[0006] Therefore, there is an urgent need for a new technical solution to solve the above technical problems. SUMMARY

[0007] The present application aims to overcome the problems of the prior art, and provides a ceramic capacitive temperature and pressure sensor, which optimizes the connection relationship between the pressure port seat, the base, the ceramic capacitor, the temperature sensing assembly, the NTC adapter plate, the electrical connector and the PFC circuit board, solves the problems of ceramic capacitor perforation damage, temperature sensing assembly support failure, poor rigidity of the PFC circuit board, sealing leakage and inefficient assembly in the prior art, and finally realizes high-precision acquisition and reliable transmission of temperature and pressure signals, while improving the anti-vibration, anti-interference and assembly and maintenance convenience of the sensor.

[0008] The above object is achieved by the following technical solutions:

[0009] A ceramic capacitive temperature and pressure sensor, comprising:

[0010] A pressure port seat, one side of which is provided with a base mounting groove, and the other side is provided with a connector; the connector is provided with a port annular groove, and the bottom wall of the port annular groove is provided with a temperature sensing assembly channel and a pressure port channel which are communicated with the base mounting groove; the pressure port seat is made of metal;

[0011] A base, which is embedded in the base mounting groove and is provided with a ceramic capacitor mounting groove on the upper surface, and the bottom wall of the ceramic capacitor mounting groove is provided with a pressure base channel which is communicated with the pressure port channel; the bottom surface of the base is provided with an NTC support column, and an NTC adapter plate embedding groove is arranged adjacent to the NTC support column; an NTC adapter terminal channel which is communicated with the upper surface of the base and the NTC adapter plate embedding groove is arranged on the side edge of the base which is symmetrical to the ceramic capacitor mounting groove, and an NTC adapter terminal is arranged in the NTC adapter terminal channel, and the two ends of the NTC adapter terminal extend out to form an NTC adapter terminal upper connecting end and an NTC adapter terminal lower connecting end;

[0012] A ceramic capacitor, which is embedded in the ceramic capacitor mounting groove and is provided with a capacitor pin on the upper surface;

[0013] A temperature sensing assembly, which is guided and supported by the NTC support column, comprising a temperature sensing needle body and an NTC thermistor connected with the temperature sensing needle body;

[0014] An NTC adapter plate, which is embedded in the NTC adapter plate embedding groove;

[0015] An electrical connector, the bottom end of which is clamped with the base and forms a PFC circuit board mounting cavity (706);

[0016] The PFC circuit board is arranged in the PFC circuit board mounting cavity, and comprises an integrally formed upper connecting portion, a lower connecting portion and an elastic flange connecting the two; the lower connecting portion is provided with a flexible supporting arm, the flexible supporting arm is provided with an NTC adapter terminal upper connecting end insertion hole for matching an NTC adapter terminal upper connecting end, and the lower connecting portion is also provided with a lower connecting portion insertion hole for penetrating a capacitor pin.

[0017] Further, the NTC support is a cylinder, is perpendicular to the base and is integrally formed, and a plurality of NTC support reinforcing ribs are arranged at the connection position of the NTC support and the base; a temperature sensing needle body embedding groove is symmetrically arranged on the NTC support, and the temperature sensing needle body is partially embedded in the temperature sensing needle body embedding groove; and a cone extension is arranged at the end of the NTC support, and a V-shaped guide groove is arranged in the cone extension and communicates with the temperature sensing needle body embedding groove.

[0018] Further, the side wall of the base is symmetrically provided with a grounding top block and symmetrically provided with a sliding groove, and a sliding buckle is arranged in the sliding groove; the bottom end of the electric connector is provided with a top block groove matched with the grounding top block and a sliding arm matched with the sliding groove, and a sliding buckle clamping groove is arranged in the sliding arm and clamped with the sliding buckle.

[0019] Further, the temperature sensing assembly further comprises a temperature sensing sheath sleeved with the temperature sensing needle body and the NTC thermistor, an annular compression sleeve is sleeved with the temperature sensing sheath, and the annular compression sleeve is in compression connection with the lower end of the temperature sensing assembly channel; the NTC thermistor is located on the central axis of the NTC support, and the length of the NTC support is less than the length of the temperature sensing needle body.

[0020] Further, the NTC adapter plate is provided with an NTC adapter terminal lower connecting end insertion hole for inserting the NTC adapter terminal lower connecting end and a temperature sensing needle body insertion hole for inserting the top end of the temperature sensing needle body; the area of the NTC adapter plate embedding groove is less than that of the ceramic capacitor mounting groove, and the NTC adapter plate embedding groove is arranged in parallel with the ceramic capacitor mounting groove.

[0021] Further, the electric connector comprises a connector outer joint and a connector terminal arranged in the connector outer joint, and the bottom end of the connector terminal extends into the PFC circuit board mounting cavity; the bottom end of the electric connector is sealed by environmental glue; and the upper connecting portion is provided with an upper connecting portion insertion hole for inserting the connector terminal.

[0022] Further, the PFC circuit board is made of a flexible base material; the upper connecting portion is provided with a flexible grounding supporting arm, and a sleeve foot is arranged at the end of the flexible grounding supporting arm; the sleeve foot is sleeved with the bottom end edge of the electric connector, and is extruded to the inner wall of the pressure port seat under the action of the grounding top block and the base mounting groove inner wall.

[0023] Further, the flexible grounding supporting arm has one of the following two structures:

[0024] One, 2 symmetrically arranged on both sides of the elastic flanging;

[0025] Two, arranged on the corresponding upper connecting part of the elastic flanging symmetric side;

[0026] The lower connecting part is octagonal, and the outer shape is not greater than the ceramic capacitor; the upper surface of the lower connecting part is provided with an electronic element mounting position.

[0027] Further, the electric connection between the capacitor pin and the lower connecting part jack, the NTC adapter terminal upper connecting end and the NTC adapter terminal upper connecting end jack, the NTC adapter terminal lower connecting end and the NTC adapter terminal lower connecting end jack, the temperature sensing needle body and the temperature sensing needle body jack, and the connector terminal and the upper connecting part jack is welded.

[0028] Further, the base mounting groove bottom wall is provided with a pressure sensing sealing ring embedding groove, and a pressure sensing sealing ring is embedded in the pressure sensing sealing ring embedding groove; the ceramic capacitor mounting groove bottom wall is provided with a ceramic capacitor sealing embedding groove, and a capacitor sealing ring is embedded in the ceramic capacitor sealing embedding groove.

[0029] The ceramic capacitor type temperature and pressure sensor provided by the application does not need to perforate the ceramic capacitor, guarantees the structural integrity to maintain the pressure sensing precision; the temperature sensing assembly is supported by the NTC pillar in layers and prevented from short circuiting by the V-shaped guide groove, the temperature detection is stable and has no deviation; the triple sealing design blocks the medium leakage and adapts to high pressure working conditions; the PFC circuit board flexible structure adapts to narrow space, and the elastic grounding arm effectively resists electromagnetic interference; the electric connector clamping design improves the assembly efficiency, and the welding reinforcement of each electric connection ensures reliable signal transmission; the whole considers the high precision of temperature and pressure detection, long-term working stability and maintenance convenience, and adapts to harsh application scenes such as high pressure and vibration. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a structure diagram of the ceramic capacitor type temperature and pressure sensor.

[0031] Figure 2 It is a sectional view of the ceramic capacitor type temperature and pressure sensor.

[0032] Figure 3 It is an assembly diagram of the electric connector and the base in the ceramic capacitor type temperature and pressure sensor.

[0033] Figure 4 It is a structure diagram of the base in the ceramic capacitor type temperature and pressure sensor.

[0034] Figure 5This is an assembly diagram of the NTC adapter terminal, base, temperature sensing component and pressure port seat in a ceramic capacitive temperature and pressure sensor according to the present invention.

[0035] Figure 6 This is an assembly diagram of the PFC circuit board, ceramic capacitor, base, and pressure port seat in a ceramic capacitive temperature and pressure sensor according to the present invention.

[0036] Figure 7 This is a schematic diagram of the electrical connections of the NTC adapter terminal, NTC adapter board, and temperature sensing component in a ceramic capacitive temperature and pressure sensor according to the present invention.

[0037] Illustration markings:

[0038] 1-Pressure port seat, 101-Base mounting groove, 102-Connector, 103-Port annular groove, 104-Temperature sensing component channel, 105-Pressure port channel, 106-Temperature sensing sealing ring groove, 107-Pressure sensing sealing ring groove;

[0039] 2-Base, 201-Ceramic capacitor mounting slot, 202-NTC support column, 203-NTC adapter plate recess, 204-NTC adapter terminal channel, 205-Pressure base channel, 206-Slide groove, 207-Slide buckle, 208-Temperature sensing needle recess, 209-Conical extension section, 210-V-shaped guide groove, 211-NTC support column reinforcing rib, 212-Ceramic capacitor sealing recess, 213-Grounding top block;

[0040] 3-NTC adapter terminal, 301-NTC adapter terminal upper connection terminal, 302-NTC adapter terminal lower connection terminal;

[0041] 4-Ceramic capacitors, 401-Capacitor pins;

[0042] 5-Temperature sensing component, 501-Temperature sensing needle, 502-NTC thermistor, 503-Temperature sensing sleeve, 504-Annular pressure sleeve;

[0043] 6-NTC adapter board, 601-NTC adapter terminal lower connection socket, 602-temperature sensing needle body socket;

[0044] 7-Electrical connector, 701-Connector external connector, 702-Connector terminal, 703-Top block recess, 704-Slide arm, 705-Slide buckle slot, 706-PFC circuit board mounting cavity;

[0045] 8-PFC circuit board, 801-Upper connection part, 802-Lower connection part, 803-Elastic flange, 804-Flexible support arm, 805-NTC adapter terminal upper connection end socket, 806-Electronic component mounting position, 807-Lower connection part socket, 808-Upper connection part socket, 809-Flexible grounding support arm, 810-Sleeve;

[0046] 9-Temperature-sensing sealing ring;

[0047] 10 - Pressure-sensitive sealing ring;

[0048] 11-Capacitor sealing ring;

[0049] 12-Environmental adhesives. Detailed Implementation

[0050] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. The described embodiments are merely some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] like Figure 1 and Figure 2 As shown, a ceramic capacitive temperature and pressure sensor is suitable for scenarios requiring simultaneous high-precision detection of temperature and pressure, such as industrial automation control, automotive air conditioning refrigerant systems, and fluid monitoring in medical equipment. It can work stably under high pressure, vibration, and confined space conditions.

[0052] like Figure 1 , Figure 2 , Figure 4 , Figure 5 and Figure 6 As shown, the connection structure between the pressure port seat 1 and the base 2 in this embodiment is as follows:

[0053] The base mounting groove 101 of the pressure port seat 1 and the base 2 are fitted together, and the base 2 is fully embedded in the mounting groove to form circumferential positioning, so as to avoid the base from shifting and causing the pressure / temperature channel to be misaligned. The pressure port seat 1 is made of metal, which has both high strength and thermal conductivity, supporting the overall structure and assisting in heat dissipation.

[0054] The pressure port channel 105 (located on the bottom wall of the port annular groove 103 of the connector 102 and the pressure base channel 205 located on the bottom wall of the ceramic capacitor mounting groove 201) is in a "straight-through" connection, and the inner wall of the channel is smooth without steps. This design avoids the pressure loss of existing curved channels, ensures that the measured medium acts directly on the bottom surface of the ceramic capacitor 4, without pressure hysteresis, and guarantees the real-time performance and accuracy of pressure detection.

[0055] The bottom wall of the base mounting groove 101 has a temperature-sensing sealing ring groove 106 and a pressure-sensing sealing ring groove 107, into which temperature-sensing sealing ring 9 and pressure-sensing sealing ring 10 are respectively embedded. The temperature-sensing sealing ring 9 surrounds the mating gap between the temperature-sensing component channel 104 and the base 2 to prevent the medium from seeping in from the temperature-sensing channel. The pressure-sensing sealing ring 10 surrounds the mating gap between the pressure port channel 105 and the base 2 to block the leakage path of the pressure medium. The double seals provide separate protection for the two independent channels of "temperature" and "pressure", avoiding overall leakage caused by the failure of a single seal, and are suitable for high-pressure operating conditions.

[0056] It should be noted that the temperature-sensing sealing ring groove 106 described in this embodiment may also be without the temperature-sensing sealing ring 9, which is used to provide sufficient space for the vertical connection between the NTC support 202 and the bottom of the base 2, especially when the NTC support reinforcing rib 211 is provided at the connection.

[0057] like Figure 2 and Figure 5 As shown, the connection structure between the base 2 and the temperature sensing component 5 in this embodiment is as follows:

[0058] The NTC support column 202 is perpendicular to the base 2 and integrally formed. This integrated structure avoids the weak connection problem of existing glue bonding or plug-in joints. In addition, the NTC support column reinforcing ribs 211 at the connection are distributed along the circumference of the support column, which can disperse vibration stress, prevent the support column from breaking, and improve long-term stability.

[0059] The temperature-sensing needle slot 208 on the NTC support 202 partially embeds the temperature-sensing needle 501, both wrapping a portion of the needle's length (this portion of the needle can be covered with an insulating layer) for guidance and not completely sealing the needle, ensuring heat exchange between the needle and the surrounding environment and avoiding temperature detection lag. The conical extension 209 and V-shaped guide groove 210 at the end of the support are designed for the V-shaped connection between the temperature-sensing needle 501 and the NTC thermistor 502: the V-shaped guide groove 210 is connected to the temperature-sensing needle slot 208, which just accommodates the V-shaped section of the needle, providing secondary support to this part to prevent the needle from shifting due to vibration, and isolating the two needles through the groove wall, structurally eliminating the risk of short circuit and solving the signal interruption problem caused by short circuit in the prior art.

[0060] The temperature-sensing sleeve 503 houses the temperature-sensing needle 501 and the NTC thermistor 502. Its top end is pressed against the lower port of the temperature-sensing component channel 104 via an annular pressure sleeve 504. The annular pressure sleeve 504 and the temperature-sensing sleeve 503 are pre-welded together. The pressing structure of the annular pressure sleeve 504 rigidly fixes the temperature-sensing sleeve 503 to the pressure port seat 1, preventing the sleeve from shifting during vibration. At the same time, the sleeve can isolate the medium from corrosion, extending the service life of the NTC thermistor 502. In addition, the NTC thermistor 502 is located on the central axis of the NTC support 202, ensuring that the thermistor is in a region with uniform medium temperature, improving the symmetry and accuracy of temperature detection.

[0061] like Figures 5-7 As shown, the connection structure between the base 2, the NTC adapter board 6, and the PFC circuit board 8 in this embodiment is as follows:

[0062] The NTC adapter board 6 is embedded in the NTC adapter board slot 203 of the base 2, forming a precise positioning. The lower connection end socket 601 of the NTC adapter terminal on the adapter board is inserted into the lower connection end 302 of the NTC adapter terminal, and the temperature sensing needle socket 602 is inserted into the top of the temperature sensing needle 501. Then, it cooperates with the flexible support arm 804 of the PFC circuit board 8 through the upper connection end 301 of the NTC adapter terminal. This intermediate path of "temperature sensing component → adapter board → adapter terminal → circuit board" completely eliminates the need for drilling holes in the ceramic capacitor 4, fundamentally protecting the structural integrity of the ceramic capacitor, avoiding stress imbalance of the pressure sensing diaphragm, and ensuring the accuracy of pressure detection. At the same time, the presence of the adapter board makes the temperature sensing signal transmission path shorter and reduces signal attenuation.

[0063] The NTC adapter board slot 203 has a smaller area than the ceramic capacitor mounting slot 201 and is set in parallel. This avoids spatial interference with the ceramic capacitor 4 on the base 2 and allows the adapter board to maintain a reasonable distance from the ceramic capacitor. This prevents the local heating of the ceramic capacitor from affecting the temperature detection of the NTC thermistor 502 and reduces cross-interference.

[0064] like Figure 2 and Figure 3 As shown, the connection structure between the electrical connector 7, the base 2, and the PFC circuit board 8 in this embodiment is as follows:

[0065] The sliding arm 704 at the bottom of the electrical connector 7 inserts into the sliding groove 206 of the base 2. During the sliding process, the sliding buckle 207 of the base 2 automatically engages with the sliding buckle groove 705 of the sliding arm 704, forming a firm fixation. Compared with existing threaded connections, this snap-fit ​​structure can complete the assembly without tools, greatly improving efficiency. At the same time, the mating gap after snap-fit ​​is sealed with environmental adhesive 12, which not only enhances the sealing performance but also further fixes the electrical connector 7, preventing it from loosening due to vibration.

[0066] The flexible grounding arm 809 of the PFC circuit board 8 has a sleeve 810 at its end that connects to the bottom edge of the electrical connector 7. During assembly, the grounding top block 213 of the base 2 and the inner wall of the base mounting groove 101 work together to press the sleeve 810 against the inner wall of the metal pressure port seat 1. This "sleeving + pressing" grounding structure eliminates the need for wire soldering, avoiding the risk of desoldering. The flexibility of the flexible grounding arm 809 can adapt to assembly deviations, ensuring that the sleeve 810 is always in close contact with the pressure port seat 1, resulting in stable grounding resistance, effectively shielding electromagnetic interference in the industrial environment, and reducing distortion of temperature and pressure signals.

[0067] The PFC circuit board 8 uses a flexible substrate. The upper connecting part 801 and the lower connecting part 802 are integrally formed by the elastic flange 803. The elastic flange 803 can absorb the stress during assembly and prevent the capacitor pin 401 from being bent due to rigid connection, thus solving the problem of pin breakage in existing circuit boards. The flexible support arm 804 of the lower connecting part 802 can deform slightly to adapt to the installation deviation of the upper connecting end 301 of the NTC adapter terminal and ensure reliable contact between the two. The lower connecting part 802 is octagonal and its shape is no larger than that of the ceramic capacitor 4, which can make full use of the space on the base 2, making the overall size of the sensor more compact and suitable for narrow installation scenarios.

[0068] like Figure 2 and Figure 6 As shown, the connection structure between the ceramic capacitor 4 and the PFC circuit board 8 in this embodiment is as follows:

[0069] The capacitor pin 401 of the ceramic capacitor 4 passes directly through the lower connection hole 807 of the lower connection part 802 of the PFC circuit board 8, forming a direct signal path of "capacitor-circuit board", reducing intermediate transfer links and reducing contact resistance; the electronic component mounting position 806 on the upper surface of the lower connection part 802 can install a signal conditioning chip. The chip is close to the capacitor pin 401, which can quickly receive and process pressure signals, reducing signal transmission delay.

[0070] In addition, all electrical connections in this solution (capacitor pins and lower connector sockets, adapter terminals and flexible support arms, adapter terminals and adapter plates, temperature sensing needles and adapter plates, connector terminals and upper connector sockets) are soldered. Soldering eliminates gaps between connections, prevents poor contact caused by vibration, further improves the reliability of signal transmission, and ensures that the sensor can still work stably under long-term vibration conditions.

[0071] Work process:

[0072] 1. Pressure signal acquisition and transmission: The measured medium enters the port annular groove 103 through connector 102. The annular groove can buffer the instantaneous impact of the medium and avoid damage to the ceramic capacitor 4 by the impact pressure. The medium then acts directly on the bottom surface of the ceramic capacitor 4 through the pressure port channel 105 and the pressure base channel 205. The straight-through channel has no pressure loss, and the medium pressure can be transmitted to the pressure-sensing diaphragm of the ceramic capacitor 4 in real time. The diaphragm deforms with the pressure, causing the capacitance value to change.

[0073] The change in capacitance is transmitted to the lower connection part 802 of the PFC circuit board 8 through the capacitor pin 401 on the upper surface of the ceramic capacitor 4. The signal conditioning chip on the electronic component mounting position 806 quickly receives the signal and performs amplification, filtering and linearization calibration. The direct connection between the capacitor pin 401 and the circuit board reduces signal attenuation, and the chip being close to the pin can reduce signal delay. The pressure detection accuracy can reach within ±0.5%FS.

[0074] 2. Temperature signal acquisition and transmission: The temperature of the measured medium is transmitted to the temperature sensing sleeve 503, which then uniformly conducts the temperature to the internal NTC thermistor 502. The sleeve isolates the medium from corrosion without hindering heat conduction, thus shortening the temperature transmission lag time.

[0075] The NTC thermistor 502 changes its resistance value with temperature. The resistance signal is transmitted to the NTC adapter board 6 through the temperature-sensing needle 501, then to the NTC adapter terminal 3, and finally to the flexible support arm 804 of the PFC circuit board 8 through the connection terminal 301 on the NTC adapter terminal. The temperature-sensing needle 501 does not shift under the support of the groove and the V-groove, and the signal transmission path is stable. The isolation effect of the V-groove ensures that there is no short circuit between the two needles and that the signal transmission is uninterrupted.

[0076] 3. Signal processing and output: The signal conditioning chip of PFC circuit board 8 combines the received pressure signal and temperature signal, performs temperature compensation on the pressure signal (eliminating the error caused by temperature change of ceramic capacitor), and finally generates an accurate temperature and pressure joint detection signal.

[0077] The detection signal is transmitted to the connector terminal 702 of the electrical connector 7 through the upper connector socket 808 of the upper connector 801, and then output to external equipment (such as automotive ECU, industrial controller) through the external connector 701. The reliable grounding of the flexible grounding arm 809 can shield electromagnetic interference, and the temperature detection error is controlled within ±0.2℃. The final output temperature and pressure signal meets the requirements of high-precision systems.

[0078] It should be noted that under vibration conditions, the reinforcing ribs of the NTC support 202 disperse stress and prevent the support from breaking; the layered support of the temperature sensing needle body 501 prevents displacement; the snap-fit ​​and glue fixation of the electrical connector 7 prevents loosening; and the elastic flange 803 absorbs vibration stress and prevents the capacitor pin from bending. All the connection structures work together to ensure that the sensor can still work stably in a vibration environment.

[0079] Under high-pressure conditions, the triple seal (temperature-sensing sealing ring, pressure-sensing sealing ring, and capacitor sealing ring) prevents the medium from leaking into the PFC circuit board mounting cavity 706; the non-perforated structure of the ceramic capacitor 4 maintains its pressure resistance, and the straight-through design of the pressure channel avoids local stress concentration, enabling this sensor to be used for a long time under high-pressure conditions without leakage or structural damage risk.

[0080] The above description is merely illustrative of the embodiments of the present invention and is not intended to limit the present invention. For those skilled in the art, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A ceramic capacitive pressure and temperature sensor, characterized by include: A pressure port seat (1) is provided with a base mounting groove (101) on one side and a connector (102) on the other side; the connector (102) is provided with a port annular groove (103), and the bottom wall of the port annular groove (103) is provided with a temperature sensing component channel (104) and a pressure port channel (105) that connect the base mounting groove (101). The base (2) has a ceramic capacitor mounting groove (201) on its upper surface and a pressure base channel (205) communicating with the pressure port channel (105) on the bottom wall of the ceramic capacitor mounting groove (201). The base (2) has an NTC support (202) on its bottom surface and an NTC adapter plate groove (203) near the NTC support (202). An NTC adapter terminal channel (204) communicating with the NTC adapter plate groove (203) is provided on the side of the base symmetrical to the ceramic capacitor mounting groove (201). An NTC adapter terminal channel (204) is provided in the NTC adapter terminal channel (204) communicating with the upper surface of the base (2) and the NTC adapter plate groove (203). An NTC adapter terminal (3) is provided in the NTC adapter terminal channel (204) and the two ends of the NTC adapter terminal (3) extend out to form an NTC adapter terminal. The NTC adapter terminal has an upper connection end (301) and an lower connection end (302); the NTC support column (202) is a cylinder, perpendicular to the base (2) and integrally formed; the NTC support column (202) is symmetrically provided with temperature sensing needle slots (208), and the temperature sensing needle slots (208) are partially embedded in the temperature sensing needle (501); the NTC support column (202) has a conical extension section (209) at its end, and the conical extension section (209) has a V-shaped guide groove (210) communicating with the temperature sensing needle slot (208); the base (2) has symmetrically provided grounding top blocks (213) on its sidewalls, and also symmetrically provided with sliding grooves (206), and the sliding grooves (206) have sliding buckles (207) in them; A ceramic capacitor (4) is embedded in the ceramic capacitor mounting slot (201) and has capacitor pins (401) on its upper surface. A temperature sensing component (5) is guided and supported by the NTC support column (202), including a temperature sensing needle body (501) and an NTC thermistor (502) connected to the temperature sensing needle body (501); the temperature sensing component (5) also includes a temperature sensing sleeve (503) covering the temperature sensing needle body (501) and the NTC thermistor (502), and an annular pressure sleeve (504) is fitted at the top of the temperature sensing sleeve (503), and the annular pressure sleeve (504) is pressed against the lower port of the temperature sensing component channel (104); the NTC thermistor (502) is located on the central axis of the NTC support column (202), and the length of the NTC support column (202) is less than the length of the temperature sensing needle body (501); An NTC adapter plate (6) is embedded in the NTC adapter slot (203); the NTC adapter plate (6) is provided with an NTC adapter terminal lower connecting end insertion hole (601) for the insertion of the NTC adapter terminal lower connecting end (302) and a temperature sensing needle insertion hole (602) for the insertion of the top end of the temperature sensing needle (501); the NTC adapter slot (203) is smaller than the ceramic capacitor mounting slot (201) and is arranged in parallel with the ceramic capacitor mounting slot (201); An electrical connector (7) is connected to the bottom of the base (2) and forms a PFC circuit board mounting cavity (706); the electrical connector (7) includes a connector external connector (701) and a connector terminal (702) arranged therein, and the bottom of the connector terminal (702) extends into the PFC circuit board mounting cavity (706); the bottom of the electrical connector (7) is sealed by environmental glue (12); the bottom of the electrical connector (7) is provided with a top block groove (703) matched with the grounding top block (213) and a sliding arm (704) matched with the sliding groove (206), and the sliding arm (704) is provided with a sliding buckle clamping groove (705) clamped with the sliding buckle (207); A PFC circuit board (8) is arranged in the PFC circuit board mounting cavity (706) and includes an integrally formed upper connecting portion (801), a lower connecting portion (802), and a flexible flange (803) connecting the two; the lower connecting portion (802) is provided with a flexible support arm (804) provided with an NTC adapter terminal upper connecting end insertion hole (805) matched with the NTC adapter terminal upper connecting end (301), and the lower connecting portion (802) is also provided with a lower connecting portion insertion hole (807) through which the capacitor insertion pin (401) penetrates; the upper connecting portion (801) is provided with an upper connecting portion insertion hole (808) for the insertion of the connector terminal (702); the PFC circuit board (8) is made of a flexible base material; the upper connecting portion (801) is provided with a flexible grounding support arm (809) provided with a sleeve foot (810) sleeved with the bottom edge of the electrical connector (7) and extruded to the inner wall of the pressure port seat (1) under the action of the grounding top block (213) and the base mounting slot (101).

2. The ceramic capacitive pressure and temperature sensor according to claim 1, characterized in that The flexible grounding support arm (809) has one of the following two structures: One, two symmetrically arranged on both sides of the flexible flange (803); Two, arranged on the corresponding symmetric side of the upper connecting portion (801) of the flexible flange (803).

3. The ceramic capacitive pressure and temperature sensor according to claim 1, wherein The electric connection between the electric capacity needle (401) and the lower connecting part jack (807), the NTC adapter terminal upper connecting end (301) and the NTC adapter terminal upper connecting end jack (805), the NTC adapter terminal lower connecting end (302) and the NTC adapter terminal lower connecting end jack (601), the temperature sensing needle body (501) and the temperature sensing needle body jack (602), the connector terminal (702) and the upper connecting part jack (808) are welded.

4. The ceramic capacitive pressure and temperature sensor of claim 1, wherein, The base mounting groove (101) is provided with a pressure sensing sealing ring groove (107) in the bottom wall, and the pressure sensing sealing ring groove (107) is embedded with a pressure sensing sealing ring (10); the ceramic capacitor mounting groove (201) is provided with a ceramic capacitor sealing groove (212) in the bottom wall, and the ceramic capacitor sealing groove (212) is embedded with a capacitor sealing ring (11).

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