Pressure sensor with high electrical strength
By setting an electrical isolation layer of the insulating layer and conductive layer inside the pressure sensor, the problem of easy breakdown of the sensor under high electrical strength is solved, good EMC performance and high electrical strength resistance are achieved, and the processability and durability of the product are ensured.
Patent Information
- Application Number
- CN202520201852.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-10
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2035-02-10
AI Technical Summary
Existing pressure sensors are prone to breakdown when facing high electrical strength, and while maintaining good EMC performance, it is difficult to take into account high electrical strength and low cost, the process is complex, and the product accuracy and durability may be sacrificed.
A high electrical strength pressure sensor is designed. By providing at least one circle of electrical isolation layers inside the sensor, including an insulating layer and a conductive layer, the conductive layer is connected to the internal circuit ground point, and the insulating layer provides high voltage electrical isolation.
The sensor's internal circuit ground shielding and high voltage electrical isolation are realized, minimizing changes to existing designs to ensure the product's processability and high durability.
Smart Images
Figure CN222689329U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of sensors, in particular to a pressure sensor with high electrical strength. Background Art
[0002] In certain applications of sensors, high electrical strength requirements are required. For example, in the commercial air conditioning industry, the product needs to withstand 1800V AC voltage without breakdown. For some sensor designs, in order to ensure good EMC performance (electromagnetic compatibility), the internal circuit needs to be electrically connected to the shell. Although this connection method can export interference, it also introduces interference paths to the product, making it easy to break down when facing high external electrical strength.
[0003] Due to installation space or cost constraints, sensors often have large size restrictions, so it is often not feasible to arrange electronic devices that withstand high voltages (such as 1800V) inside the sensor. There are different product solutions on the market to achieve both good EMC performance and high electrical strength. For example, a metal cup is placed outside the electrical assembly as a whole and fixed together in advance, and then a layer of insulating paper is added between the assembly and the final housing to achieve electrical isolation, or a flexible board is used and the flexible board is wrapped around the electrical sensitive device. Although the needs of electrical strength and electrical performance are met at the same time, these solutions are either complicated in process, high in cost, or sacrifice product performance such as precision and durability. Utility Model Content
[0004] The utility model aims to overcome the defects of the prior art and provides a pressure sensor with high electrical strength to improve the processability and durability of the pressure sensor.
[0005] In order to achieve the above purpose and other purposes, the utility model is implemented by including the following technical solutions: The utility model provides a high electrical strength pressure sensor, the pressure sensor comprising: a shell, the shell is provided with an inner cavity and a pressure-sensitive channel, the pressure-sensitive channel and the inner cavity are connected; a pressure-sensitive core is arranged in the inner cavity; a circuit board is arranged in the inner cavity, one end of the circuit board is connected to the pressure-sensitive core; a connector, the connector comprises a connector body and a conductive member located in the connector body, one end of the connector body is connected to one end of the shell, and one end of the conductive member is connected to the other end of the circuit board; a conductive layer is located in the inner cavity and is arranged on the periphery of the circuit board and the pressure-sensitive core, the conductive layer is at least partially in contact with the circuit board; and an insulating layer is located in the inner cavity and coated on the periphery of the conductive layer.
[0006] In some embodiments, the bottom of the inner cavity of the shell has a first groove and a second groove, the first groove is located outside the pressure sensing channel, the second groove is located outside the first groove, and a first sealing ring is disposed in the first groove.
[0007] In some embodiments, the pressure-sensitive core is located on the first sealing ring.
[0008] In some embodiments, the bottom end of the insulating layer is disposed in the second groove, and the top ends of the insulating layer and the conductive layer are disposed at the top of the inner cavity.
[0009] In some embodiments, the top ends of the insulating layer and the conductive layer have a first folded edge and a second folded edge respectively, and the width of the first folded edge is greater than the width of the second folded edge.
[0010] In some embodiments, one end of the second folded edge contacts a ground terminal on the circuit board.
[0011] In some embodiments, the bottom end of the connector body has a receiving cavity, and the circuit board is at least partially located in the receiving cavity.
[0012] In some embodiments, a side wall of the accommodating cavity has a notch, and the grounding end of the circuit board extends out of the notch.
[0013] In some embodiments, the insulating layer is a polymer plastic layer, and the conductive layer is a metal conductive layer.
[0014] The utility model provides a pressure sensor. Compared with the prior art, the utility model has the following beneficial effects: the pressure sensor adds at least one circle of electrical isolation layer on the basis of the prior art, and the electrical isolation layer is composed of an insulating layer and a conductive layer, wherein the conductive layer is used to connect to the grounding point of the internal circuit and plays the role of electromagnetic shielding. The outer insulating layer plays the role of electrical isolation of high voltage. A stable contact of shell-insulating layer-conductive layer-internal circuit is formed on the sensor. Thereby, the grounding shielding of the internal circuit and the electrical isolation of the high voltage are realized. While realizing the grounding and electrical isolation of the electrical components, the changes to the existing design are minimized to the greatest extent, thereby also ensuring the processability and high durability of the product. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 Shown is a schematic structural diagram of the pressure sensor of the utility model.
[0016] Figure 2 Shown is a cross-sectional view of the pressure sensor of the present invention.
[0017] Figure 3 Shown is a schematic diagram of the explosion structure of the pressure sensor of the utility model.
[0018] Figure 4 Shown is a schematic diagram of the contact structure between the circuit board and the conductive layer of the utility model.
[0019] Figure 5 Shown is a schematic structural diagram of the housing of the utility model.
[0020] Numbers in the figure:
[0021] 1-shell, 11-inner cavity, 11a-first groove, 11b-second groove, 12-pressure sensing channel, 13-third folded edge;
[0022] 2-connector, 21-connector body, 21a-accommodating cavity, 21b-notch, 22-conducting member;
[0023] 3- first sealing ring;
[0024] 4-Pressure-sensitive core;
[0025] 5-circuit board, 51-ground terminal;
[0026] 6-insulating layer, 61-first folded edge;
[0027] 7-conductive layer, 71-second folded edge;
[0028] 8- Second sealing ring. DETAILED DESCRIPTION
[0029] See also Figures 1 to 5 The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and functions of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.
[0030] like Figure 1 and Figure 2 As shown, the utility model provides a pressure sensor, which includes a shell 1. The shell 1 is a metal shell 1. The shell 1 has an inner cavity 11 and a pressure sensing channel 12. The pressure sensing channel 12 is communicated with the inner cavity 11.
[0031] like Figure 2 and Figure 5As shown, the bottom of the inner cavity 11 has a first groove 11a, and the first sealing ring 3 is arranged in the first groove 11a. The first sealing ring 3 can prevent the medium in the pressure sensing channel 12 from penetrating into the sensor. The first groove 11a is located at the periphery of the pressure sensing channel 12. The bottom of the inner cavity 11 also has a second groove 11b, and the second groove 11b is located between the side wall of the inner cavity 11 and the first groove 11a. The housing 1 has a hexagonal structure.
[0032] like Figure 2 and Figure 3 As shown, the pressure sensor includes a pressure-sensitive core 4, which is located in the inner cavity 11. The bottom of the pressure-sensitive core 4 is at least partially connected to the pressure-sensitive channel 12. The pressure-sensitive core 4 is located on the first sealing ring 3. The pressure-sensitive core 4 can be a pressure-sensitive core 4 of a ceramic diaphragm. The pressure-sensitive core 4 can be slightly deformed by the pressure of the medium in the pressure-sensitive channel 12. The displacement deformation signal change is transmitted to the chip on the circuit board 5 and corresponding signal processing is performed. Finally, the pressure signal is output through the conductive member 22.
[0033] like Figure 3 and Figure 4 As shown, the pressure sensor includes a circuit board 5 arranged in the inner cavity 11, and the circuit board 5 can be a flexible circuit board 5. One end of the circuit board 5 can be connected to the pressure-sensing core 4, and the connection can be welding. The circuit board 5 has a grounding terminal 51 at one end close to the connector 2, and the grounding terminal 51 can contact the shell 1 and the second folded edge 71.
[0034] like Figure 2 and Figure 3 As shown, the pressure sensor includes a connector 2, the connector 2 includes a connector body 21 and a conductive member 22 located in the connector body 21, one end of the conductive member 22 is electrically connected to the circuit board 5, for example, it can be welded. The bottom end of the connector 2 is at least partially located in the inner cavity 11, and specifically the bottom end of the connector 2 is connected to the top end of the housing 1, and the connection method can be a riveting connection, for example, the top of the housing 1 is bent to form a third fold 13, the connector body 21 can be a plastic part, the bottom end of the connector body 21 has a receiving cavity 21a, the receiving cavity 21a can accommodate part of the circuit board 5, the top end of the conductive member 22 is located in the connector port of the connector body 21, and the bottom end of the conductive member 22 extends into the receiving cavity 21a to be welded to the circuit board 5. The side wall of the receiving cavity 21a has a notch 21b, and the notch 21b can provide a grounding contact channel for the circuit board 5.
[0035] like Figure 2 and Figure 4 As shown, the pressure sensor includes an insulating layer 6, the insulating layer 6 is located in the inner cavity 11, the bottom end of the insulating layer 6 is located in the second groove 11b, and the top end of the insulating layer 6 is arranged at the inner side wall of the top of the inner cavity 11 of the shell 1. Specifically, the top end of the insulating layer 6 has a first folded edge 61, and the first folded edge 61 is in contact with the shell 1. The insulating layer 6 can be made of polyimide PI.
[0036] like Figure 2 and Figure 4 As shown, the pressure sensor includes a conductive layer 7, and the conductive layer 7 can be arranged on the periphery of the circuit board 5 and the pressure-sensitive core 4. Further, the conductive layer 7 can be arranged on the periphery of the connector body 21. The conductive layer 7 is located in the inner cavity 11. The conductive layer 7 is arranged on one side surface of the insulating layer 6 and is located on the side close to the first groove 11a. Specifically, the conductive layer 7 is covered by the insulating layer 6, and the conductive layer 7 is at least partially in contact with the circuit board 5. Specifically, the top of the conductive layer 7 is arranged at the inner side wall of the top of the inner cavity 11 of the shell 1, and the top of the conductive layer 7 has a second folded edge 71, the width of the first folded edge 61 is greater than the width of the second folded edge 71, and the second folded edge 71 is in contact with the circuit board 5. The conductive layer 7 can be a metal layer, and the metal layer can be made of copper. The insulating layer 6 and the conductive layer 7 are hollow cylinders.
[0037] like Figure 3 and Figure 4 As shown, the grounding end 51 of the circuit board 5 extends out of the notch 21 b and contacts the second folded edge 71 at the top of the conductive layer 7 to achieve electrical connection.
[0038] like Figure 1 As shown, the bottom end of the housing 1 is sleeved with a second sealing ring 8, and the second sealing ring 8 can form a certain sealing performance with the pipeline of the detection medium.
[0039] The installation of the utility model may include: rolling up the conductive layer 7 and the insulating layer 6 and placing them in the inner cavity 11 of the shell, placing the first sealing ring 3 and the pressure-sensitive core 4 and pre-assembling them with the circuit board 5 and the connector 2, reliably connecting the circuit board 5 and the pressure-sensitive core 4 and the conductive part 22 on the connector 2 together through automatic welding, and finally bending the top of the shell 1 through a crimping process to form a third folded edge 13 and connect it to the connector 2 to complete the assembly.
[0040] Therefore, the utility model effectively overcomes various shortcomings in the prior art and has a high industrial utilization value. The above embodiments are only illustrative of the principles and effects of the utility model, and are not used to limit the utility model. Anyone familiar with this technology can modify or change the above embodiments without violating the spirit and scope of the utility model. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the relevant technical field without departing from the spirit and technical ideas disclosed by the utility model should still be covered by the claims of the utility model.
Claims
1. A pressure sensor with high electrical strength, characterized in that: The pressure sensor comprises: A housing, wherein an inner cavity and a pressure-sensing channel are provided in the housing, and the pressure-sensing channel is communicated with the inner cavity; A pressure-sensitive core body is arranged in the inner cavity; A circuit board is arranged in the inner cavity, and one end of the circuit board is connected to the pressure-sensitive core; A connector, the connector comprising a connector body and a conductive member located in the connector body, one end of the connector body is connected to one end of the housing, and one end of the conductive member is connected to the other end of the circuit board; A conductive layer, located in the inner cavity and arranged on the periphery of the circuit board and the pressure-sensitive core, wherein at least a portion of the conductive layer is in contact with the circuit board; and an insulating layer, which is located in the inner cavity and covers the outer periphery of the conductive layer.
2. The high electrical strength pressure sensor according to claim 1, characterized in that: The bottom of the inner cavity of the shell has a first groove and a second groove, the first groove is located at the periphery of the pressure sensing channel, the second groove is located at the periphery of the first groove, and a first sealing ring is arranged in the first groove.
3. The high electrical strength pressure sensor according to claim 2, characterized in that: The pressure-sensitive core is located on the first sealing ring.
4. The high electrical strength pressure sensor according to claim 2, characterized in that: The bottom end of the insulating layer is arranged in the second groove, and the top ends of the insulating layer and the conductive layer are arranged on the top of the inner cavity.
5. The pressure sensor with high electrical strength according to claim 1, characterized in that: The top ends of the insulating layer and the conductive layer have a first folded edge and a second folded edge respectively, and the width of the first folded edge is greater than the width of the second folded edge.
6. The pressure sensor with high electrical strength according to claim 5, characterized in that: One end of the second folded edge contacts a ground terminal on the circuit board.
7. The pressure sensor with high electrical strength according to claim 6, characterized in that: The bottom end of the connector body is provided with a receiving cavity, and the circuit board is at least partially located in the receiving cavity.
8. The pressure sensor with high electrical strength according to claim 7, characterized in that: A notch is provided on the side wall of the accommodating cavity, and the grounding end of the circuit board extends out of the notch.
9. The pressure sensor with high electrical strength according to claim 1, characterized in that: The insulating layer is a polymer plastic layer, and the conductive layer is a metal conductive layer.