An open type ceramic pressure and temperature sensor capable of preventing impurities from being deposited

Abstract

The utility model relates to an open type ceramic pressure temperature sensor capable of preventing impurity deposition, which is internally provided with a printed board, a ceramic pressure sensing core, a ceramic carrier sheet, an insulating protective tube and a thermistor. A groove seat facing the ceramic carrier sheet is formed on the ceramic pressure sensing core, a pressure sensing diaphragm is arranged in the groove seat, an upper O-shaped ring is arranged between the ceramic carrier sheet and the pressure sensing diaphragm, and a conductive spring connecting the printed board and the ceramic carrier sheet is further arranged in the ceramic pressure sensing core to realize the transmission of the thermistor signal. The ceramic pressure sensing core replaces the traditional embedded plastic carrier to reduce the number of intermediate carriers. The ceramic carrier sheet is provided with a conductive silk screen; and the ceramic base is provided with a first through hole for passing through the thermistor pin and a second through hole for discharging impurities. Through the second through hole, the machining debris and the pollutants in the medium in the pipeline can be directly discharged outside the sensor through the insulating protective tube, the deposition of impurities on the ceramic carrier sheet is prevented, and the short circuit of the thermistor pin is avoided.

Description

Technical Field

[0001] This utility model relates to the field of pressure and temperature sensor technology, and in particular to an open-type ceramic pressure and temperature sensor that can prevent impurity deposition. Background Technology

[0002] Most ceramic pressure-temperature sensors used in non-conductive media require a plastic clamp to connect to the thermistor, bypassing the O-ring and pressure-sensing core before being soldered again to transmit the signal. When the clamp is used for injection molding, the difference in thermal expansion rates between the clamp metal and plastic can create gaps between them during temperature changes. This allows impurities such as processing debris to penetrate into the product, causing sensor seal failure. Furthermore, open-type pressure-temperature sensors may experience short circuits due to contamination in the piping, affecting the accuracy of the thermistor signal. Utility Model Content

[0003] To address the problem in existing technologies where gaps between the clamp and the plastic allow impurities to penetrate into the product and affect the accuracy of the thermistor signal, this invention provides an open-type ceramic pressure and temperature sensor that prevents impurity deposition. The sensor includes a socket and a metal housing, which are connected by an encapsulation. The internal space formed by the socket and the metal housing, from top to bottom, includes a printed circuit board, a ceramic pressure-sensing core, a ceramic carrier plate, and an insulating protective tube. The thermistor is housed within the insulating protective tube.

[0004] The ceramic carrier sheet includes a ceramic substrate, on which conductive silkscreen is provided for contact with the thermistor pins; the ceramic substrate has a first through hole for passing through the thermistor pins and a second through hole for discharging impurities, the second through hole being located close to the first through hole; the second through hole is connected to one end of the insulating protective tube, the other end of the insulating protective tube being located outside the metal casing;

[0005] The ceramic pressure-sensitive core has a groove facing the ceramic carrier plate. A pressure-sensitive diaphragm is provided in the groove. An upper O-ring is provided between the ceramic carrier plate and the pressure-sensitive diaphragm. The sum of the thicknesses of the pressure-sensitive diaphragm and the upper O-ring is greater than the depth of the groove. The ceramic pressure-sensitive core also has a third through hole. A conductive spring with its two ends connected to the printed circuit board and the conductive screen printing is provided in the third through hole.

[0006] Furthermore, a lower O-ring for sealing is provided between the ceramic carrier plate and the bottom of the metal shell.

[0007] Furthermore, the pins of the thermistor are soldered to the first through hole.

[0008] Furthermore, the ceramic carrier plate is provided with a buckle for assembly, and the socket is provided with a claw for engaging with the buckle.

[0009] Furthermore, a layer of glass glaze is also provided on the conductive silkscreen.

[0010] Compared with the prior art, this utility model has the following beneficial effects:

[0011] This invention replaces the traditional insert plastic carrier with a ceramic pressure-sensitive core, and incorporates a conductive spring within the ceramic pressure-sensitive core to connect the printed circuit board and the conductive ceramic carrier plate, thus enabling the transmission of thermistor signals. The novel internal structure design reduces the number of intermediate carriers, avoiding the gaps that easily form between clamps and plastic in existing technologies. Furthermore, by opening a second through-hole near the thermistor pins, processing debris from the manufacturing process and contaminants from the pipeline during use can be directly discharged to the outside of the sensor through an insulating protective tube, effectively preventing impurities from depositing on the ceramic carrier plate and avoiding short circuits at the thermistor pins. In addition, O-rings are placed on both the top and bottom of the ceramic carrier plate for product sealing, so the impact of temperature changes on the sealing structure is almost negligible. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application;

[0013] Figure 2 This is an exploded view of an embodiment of this application;

[0014] Figure 3 This is a schematic diagram of the ceramic carrier sheet structure according to an embodiment of this application;

[0015] Figure 4 This is a schematic diagram of the ceramic pressure-sensitive core structure according to an embodiment of this application;

[0016] In the diagram: 1. Thermistor; 2. Ceramic carrier plate; 20. Ceramic substrate; 21. Conductive screen printing; 22. Glass glaze; 23. First through hole; 24. Second through hole; 25. Snap-on; 3. Socket; 31. Claw; 4. Ceramic pressure-sensitive core; 41. Pressure-sensitive diaphragm; 42. Concave thick sheet; 43. Third through hole; 5. Conductive spring; 6. Metal casing; 7. Lower O-ring; 8. Insulating protective tube; 9. Upper O-ring; 10. Printed circuit board. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0018] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The terms "upper," "lower," "front," "rear," "top," "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or part referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. It should be understood that such data can be interchanged where appropriate for the embodiments of this utility model described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0019] like Figure 1 and Figure 2 As shown, an open-type ceramic pressure and temperature sensor that can prevent impurity deposition includes a socket 3 and a metal housing 6. The socket 3 and the metal housing 6 are connected by an encapsulation. The internal space formed by the socket 3 and the metal housing 6 includes, from top to bottom, a printed circuit board 10, a ceramic pressure-sensing core 4, a ceramic carrier plate 2, and an insulating protective tube 8. A thermistor 1 is provided inside the insulating protective tube 8.

[0020] like Figure 3 As shown, the ceramic carrier plate 2 includes a ceramic substrate 20, on which a conductive silkscreen 21 is provided that contacts the pins of the thermistor 1. The ceramic substrate 20 has a first through-hole 23 for the thermistor 1 pins to pass through and a second through-hole 24 for discharging impurities. The second through-hole 24 is located close to the first through-hole 23. The second through-hole 24 is connected to one end of an insulating protective tube 8, the other end of which is located outside the metal casing 6. Through the second through-hole 24, processing debris during production and contaminants from the medium in the pipeline during use can be directly discharged outside the sensor through the insulating protective tube 8, effectively preventing impurities from depositing on the ceramic carrier plate 2 and avoiding short circuits in the pins of the thermistor 1.

[0021] like Figure 4As shown, the ceramic pressure-sensitive core 4 has a groove 42 facing the ceramic carrier plate 2. A pressure-sensitive diaphragm 41 is placed inside the groove 42, and an upper O-ring 9 is positioned between the ceramic carrier plate 2 and the pressure-sensitive diaphragm 41. To ensure sealing performance, the combined thickness of the pressure-sensitive diaphragm 41 and the upper O-ring 9 is greater than the depth of the groove 42. The ceramic pressure-sensitive core 4 also has a third through-hole 43, within which a conductive spring 5, with its two ends connected to the printed circuit board 10 and the conductive screen printing 21 respectively, is located. The conductive spring 5 in the third through-hole 43 transmits the temperature signal from the thermistor to the printed circuit board 10 above the ceramic pressure-sensitive core 4, thus realizing the transmission of the thermistor signal. This irregularly shaped ceramic pressure-sensitive core 4 replaces the traditional insert plastic carrier, reducing the number of intermediate components inside the sensor.

[0022] To ensure the product's airtightness, a lower O-ring 7 is provided between the ceramic carrier plate 2 and the bottom of the metal shell 6.

[0023] In one implementation, the pins of the thermistor 1 are soldered to the first through hole 23.

[0024] like Figure 2 and Figure 3 As shown, the ceramic carrier plate 2 is provided with snap fasteners 25 for assembly, and the socket 3 is provided with claws 31 for engaging with the snap fasteners 25. In this embodiment, the ceramic carrier plate 2 has two snap fasteners on both sides. In this way, the socket 3 tightly presses the printed circuit board 10, the ceramic pressure-sensitive core 4 and the ceramic carrier plate 2 together.

[0025] As a preferred implementation method, such as Figure 4 As shown, a layer of glass glaze 22 is also provided on the conductive silkscreen 21. By covering the conductive layer (i.e., the conductive silkscreen 21) with a layer of glass glaze 22 as the sealing surface of the upper O-ring 9, the problem of unevenness of the conductive silkscreen 21 can be solved.

[0026] Before product assembly, a conductive screen printing layer 21 needs to be printed and sintered on the ceramic substrate 20, and then a glass glaze 22 needs to be printed and sintered again to form a conductive ceramic carrier sheet 2.

[0027] During product assembly, firstly, an insulating protective tube 8 and a lower O-ring 7 are placed at the bottom of the metal casing 6. Next, the thermistor 1 is soldered onto the ceramic carrier plate 2 through the first through hole 23. The upper O-ring 9 and the ceramic pressure-sensitive core 4 are then placed sequentially on the ceramic carrier plate 2, and a conductive spring 5 is placed in the third through hole 43. Then, the socket 3 is assembled from top to bottom using the cutout, allowing the claws 31 to engage with the clips 25 on both sides of the ceramic carrier plate 2, thus assembling the socket 3, printed circuit board 10, ceramic pressure-sensitive core 4, ceramic carrier plate 2, and the thermistor 1 into a single unit. Finally, the entire assembly is placed inside the metal casing 6, with the thermistor 1 positioned inside the insulating protective tube 8, thus encapsulating the socket 3 with the metal casing 6.

[0028] The above description is merely a preferred embodiment of this utility model and is not intended to limit the scope of implementation of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and all such improvements and modifications should be covered within the protection scope of this utility model.

Claims

1. An open-type ceramic pressure and temperature sensor that prevents impurity deposition, comprising a socket (3) and a metal housing (6), wherein the socket (3) and the metal housing (6) are connected by an encapsulation, characterized in that, The internal space formed by the socket (3) and the metal shell (6) includes, from top to bottom, a printed circuit board (10), a ceramic pressure-sensitive core (4), a ceramic carrier plate (2), and an insulating protective tube (8); a thermistor (1) is provided inside the insulating protective tube (8); The ceramic carrier plate (2) includes a ceramic substrate (20), on which a conductive silkscreen (21) is provided that contacts the pin of the thermistor (1); the ceramic substrate (20) has a first through hole (23) for passing through the pin of the thermistor (1) and a second through hole (24) for discharging impurities, the second through hole (24) being opened close to the first through hole (23); the second through hole (24) is connected to one end of the insulating protective tube (8), and the other end of the insulating protective tube (8) is located outside the metal shell (6); The ceramic pressure-sensitive core (4) has a groove seat (42) facing the ceramic carrier plate (2). A pressure-sensitive diaphragm (41) is provided in the groove seat (42). An upper O-ring (9) is provided between the ceramic carrier plate (2) and the pressure-sensitive diaphragm (41). The sum of the thicknesses of the pressure-sensitive diaphragm (41) and the upper O-ring (9) is greater than the depth of the groove seat (42). The ceramic pressure-sensitive core (4) also has a third through hole (43). A conductive spring (5) with its two ends connected to the printed circuit board (10) and the conductive screen printing (21) is provided in the third through hole (43).

2. The open-type ceramic pressure and temperature sensor with impurity-preventing properties according to claim 1, characterized in that, A lower O-ring (7) for sealing is provided between the ceramic carrier plate (2) and the bottom of the metal shell (6).

3. The open-type ceramic pressure and temperature sensor that prevents impurity deposition according to claim 1, characterized in that, The pins of the thermistor (1) are soldered to the first through hole (23).

4. An open-type ceramic pressure and temperature sensor capable of preventing impurity deposition according to claim 1, characterized in that, The ceramic carrier plate (2) is provided with a buckle (25) for assembly, and the socket (3) is provided with a claw (31) for engaging with the buckle (25).

5. An open-type ceramic pressure and temperature sensor capable of preventing impurity deposition according to claim 1, characterized in that, The conductive silkscreen (21) is also provided with a layer of glass glaze (22).

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