Pressure sensor based on spring needle electrical connection

Abstract

The utility model relates to a pressure sensor based on spring needle electrical connection, which comprises a sensing element, a PCB (printed circuit board), a support ring and a fixing framework, the fixing framework is provided with circumferentially distributed plugging holes, and spring needles are clamped in the plugging holes; the spring needle comprises a needle tube clamped in the inserting hole in a limited mode, an upper needle shaft is arranged at the upper end of an inner hole of the needle tube in a sliding mode, a lower needle shaft is arranged at the lower end of the inner hole of the needle tube in a sliding mode, the lower needle shaft is in contact connection with the PCB, and the upper needle shaft is in attached contact with an electric connection contact on a circuit board of a used device. And a spring is arranged in the needle tube between the upper needle shaft and the lower needle shaft. According to the utility model, the upper pin shaft is pushed by the spring of the spring pin, and the lower pin shaft and the electric connection contact on the corresponding circuit board are connected in an attached contact manner, so that compared with the existing connection manner that the connection terminal needs to be inserted into a jack on the circuit board of equipment to realize electric connection, more installation space can be saved; and the use requirement in a narrower space is met.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a pressure sensor based on spring pin electrical connection. Background Art

[0002] A pressure sensor is one of the most commonly used sensors in industrial practice. It senses a pressure signal and converts the pressure signal into an electrical signal output according to a certain rule. A pressure sensor usually consists of a pressure-sensitive element and a signal processing unit.

[0003] At present, for the electrical connection between most pressure sensors and device circuit boards, connectors, springs, etc. are mostly used to achieve electrical connection. Although the electrical connection method using connectors is very common, it is not suitable for use in occasions with relatively small space; if the spring contact method is used, although the problem of space layout can be solved, the spring is prone to poor contact and is easily bent and broken, resulting in a high failure rate.

[0004] Therefore, an electrical connection method using a fish-eye pin terminal has emerged. Through the snap-fit cooperation between the connection terminal and the fixed skeleton, it solves the problems that the spring is prone to bending and breaking and has a high failure rate when the traditional sensor uses the spring connection method, and is suitable for mass production.

[0005] However, when the fish-eye pin connection terminal of this structure is electrically connected to the device circuit board, it is achieved by inserting the contact part of the connection terminal into the jack on the device circuit board. Since the connection terminal is a rigid structure, this plug-in connection method still cannot meet the requirements for use in a smaller space. Content of the Utility Model

[0006] The technical problem to be solved by the utility model is: in order to overcome the deficiencies in the prior art, the utility model provides a pressure sensor based on spring pin electrical connection that can meet the requirements for use in a smaller space.

[0007] The technical solution adopted by the utility model to solve its technical problems is: a pressure sensor based on spring pin electrical connection, including a sensing element, a PCB circuit board and a support ring. The PCB circuit board is fixed to the upper end of the support ring, the sensing element extends into the support ring, a silicon-based strain gauge electrically connected to the PCB circuit board is provided on the upper end surface of the sensing element, a fixed skeleton is provided above the PCB circuit board, and circumferentially distributed insertion holes are formed in the fixed skeleton, and spring pins are clamped in the insertion holes; the spring pin includes a needle tube limitedly clamped in the insertion hole, an upper needle shaft is slidably arranged at the upper end of the inner hole of the needle tube, a lower needle shaft is slidably arranged at the lower end of the inner hole of the needle tube, the lower needle shaft is in contact connection with the PCB circuit board, the upper needle shaft is in close contact with the electrical connection contact on the device circuit board to be used, and a spring is arranged in the needle tube between the upper needle shaft and the lower needle shaft.

[0008] The middle part of the outer wall surface of the syringe needle tube has an annular boss, and the insertion hole is a stepped hole with a smaller upper part and a larger lower part. The upper plane of the annular boss abuts against the stepped surface of the insertion hole to limit the upward movement of the spring needle.

[0009] The contact surfaces of the upper needle shaft, the lower needle shaft and the spring are all inclined surfaces.

[0010] It has a housing, and the housing has a cavity extending along the length direction of the housing and opening at both ends. The support ring assembled with the PCB circuit board and the sensing element is installed in the inner cavity of the housing, and the fixed skeleton is located in the inner cavity of the housing above the PCB circuit board.

[0011] The side walls of the sensing element are respectively provided with a first step and a second step. The circumferential end of the lower end of the housing abuts against the first step and is fixed to the first step, and the circumferential end of the lower end of the support ring abuts against the second step and is fixed to the second step.

[0012] The outer wall of the middle part of the fixed skeleton has a boss, the circumferential wall at the upper end of the housing is bent inward and abuts against the boss, and the bottom of the side of the fixed skeleton has a hook supported on the bottom surface of the upper layer board of the PCB circuit board.

[0013] The PCB circuit board is electrically connected to the silicon-based strain gauge through five aluminum wires.

[0014] The beneficial effects of the present utility model are as follows: Through the spring force of the spring needle of the present utility model, a fitting contact connection method is formed between the upper needle shaft, the lower needle shaft and the electrical connection contacts on the corresponding circuit board. Compared with the connection method in the existing pressure sensor where the connection terminal needs to be inserted into the jack on the device circuit board for electrical connection, more installation space can be saved, meeting the usage requirements in a narrower space. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0016] Figure 1 is a schematic diagram of the external structure of the present utility model.

[0017] Figure 2 is a schematic cross-sectional structure diagram of the present utility model.

[0018] Figure 3 is a three-dimensional structure diagram of the sensing element of the present utility model.

[0019] Figure 4 is an installation schematic diagram of the PCB circuit board and the support ring of the present utility model.

[0020] Figure 5 is a schematic cross-sectional structure diagram of the fixed skeleton of the present utility model.

[0021] Figure 6 It is a schematic structural view of the spring pin of the present utility model.

[0022] In the figure: 10. Sensing element, 11. Silicon-based strain gauge, 12. First step, 13. Second step, 20. Support ring, 30. PCB circuit board, 40. Fixed skeleton, 41. Insertion hole, 42. Hook, 50. Spring pin, 51. Needle tube, 52. Upper needle shaft, 53. Lower needle shaft, 54. Spring, 55. Annular boss, 60. Outer shell, 70. Aluminum wire. Specific embodiments

[0023] Now, the present utility model will be further described in detail with reference to the accompanying drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present utility model in a schematic manner, so they only show the components related to the present utility model.

[0024] As Figures 1 to 4 shown, a pressure sensor based on spring pin electrical connection includes an outer shell 60, a sensing element 10, a PCB circuit board 30 and a support ring 20. The outer shell 60 has an inner cavity extending along the length direction of the outer shell 60 and opening at both ends. The PCB circuit board 30 is fixed to the upper end of the support ring 20. The sensing element 10 extends into the support ring 20. A silicon-based strain gauge 11 electrically connected to the PCB circuit board 30 through five aluminum wires 70 is provided on the upper end surface of the sensing element 10. The support ring 20 assembled with the PCB circuit board 30 and the sensing element 10 is inserted into the inner cavity of the outer shell 60.

[0025] The sensing element 10 has a pressure cavity with an opening at the bottom. After the fluid enters the pressure cavity from the opening at the bottom of the sensing element 10, the bottom wall of the pressure cavity is pressed to deform, thereby driving the silicon-based strain gauge 11 to deform.

[0026] First steps 12 and second steps 13 are respectively provided on the outer side wall of the sensing element 10. The lower circumferential end of the outer shell 60 is pressed against the first step 12 and welded and fixed to the first step 12. The lower circumferential end of the support ring 20 is pressed against the second step 13 and welded and fixed to the second step 13.

[0027] To prevent the outer shell 60 from deforming under external forces and squeezing the support ring 20, thereby squeezing the sensing element 10 and causing damage to the sensing element 10, a gap is provided between the outer side wall of the support ring 20 and the inner side wall of the inner cavity of the outer shell 60, and a gap is provided between the outer circumference of the sensing element 10 extending into the support ring 20 and the inner side wall of the support ring 20.

[0028] Inside the inner cavity of the housing 60 located above the PCB circuit board 30, a fixed skeleton 40 is installed. The upper half of the fixed skeleton 40 extends outside the inner cavity of the housing 60. There is a boss on the outer wall of the middle part of the fixed skeleton 40. The upper peripheral wall of the housing 60 is bent inward and pressed against the boss. At the bottom of the side of the fixed skeleton 40, there is a hook 42 that supports the bottom surface of the upper layer board of the PCB circuit board 30.

[0029] As Figure 2 , Figure 5 shown, four insertion holes 41 distributed circumferentially are formed on the fixed skeleton 40. The insertion holes 41 are stepped holes that are smaller at the top and larger at the bottom. A spring pin 50 for electrical connection is clamped in each insertion hole 41.

[0030] Refer to Figure 6 shown, the spring pin 50 includes a needle tube 51, an upper needle shaft 52, a lower needle shaft 53 and a spring 54. An annular boss 55 is provided in the middle of the outer wall surface of the needle tube 51. The spring pin 50 is inserted into the large hole at the bottom of the insertion hole 41, and the upper plane of the annular boss 55 abuts against the stepped surface of the insertion hole 41, so as to control the upward movement of the spring pin 50 during use.

[0031] The spring 54 is arranged inside the needle tube 51. The upper needle shaft 52 is slidably arranged at the upper end of the inner hole of the needle tube 51 and the contact head of the upper needle shaft 52 extends outside the upper end of the needle tube 51. The lower needle shaft 53 is slidably arranged at the lower end of the inner hole of the needle tube 51 and the contact head of the lower needle shaft 53 extends outside the lower end of the needle tube 51. The upper end of the spring 54 abuts against the inner end surface of the upper needle shaft 52, and the lower end of the spring 54 abuts against the inner end surface of the lower needle shaft 53. Moreover, the inner end surfaces of the upper needle shaft 52 and the lower needle shaft 53 in contact with the spring 54 are both inclined surfaces.

[0032] The contact head of the lower needle shaft 53 is in close contact with the electrical connection contact on the PCB circuit board 30, and the upper needle shaft 52 is in close contact with the electrical connection contact on the circuit board of the used device. For the pressure sensor with such a structure, the electrical connection is realized by the spring pin 50. Relying on the acting force of the spring 54, a connection method of close contact is formed between the upper needle shaft 52, the lower needle shaft 53 and the electrical connection contacts on the corresponding circuit boards. Compared with the connection method in the existing pressure sensors, where the connection terminals need to be inserted into the jacks on the device circuit boards to achieve electrical connection, more installation space can be saved, meeting the use requirements in a narrower space.

[0033] Inspired by the above ideal embodiments based on the present invention, through the above description, relevant staff can completely make various changes and modifications within the scope not deviating from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A pressure sensor based on spring pin electrical connection, comprising a sensing element (10), a PCB circuit board (30) and a support ring (20), wherein the PCB circuit board (30) is fixed to the upper end of the support ring (20), the sensing element (10) extends into the support ring (20), a silicon-based strain gauge (11) electrically connected to the PCB circuit board (30) is provided on the upper end surface of the sensing element (10), and a fixed frame (40) is provided above the PCB circuit board (30), wherein the characteristics are: The fixed frame (40) is provided with circumferentially distributed plug holes (41), and spring pins (50) are mounted inside the plug holes (41); The spring needle (50) comprises a needle tube (51) which is limitedly clamped in the plug hole (41); an upper needle shaft (52) is slidably provided at the upper end of the inner hole of the needle tube (51); a lower needle shaft (53) is slidably provided at the lower end of the inner hole of the needle tube (51); the lower needle shaft (53) is in contact with a PCB circuit board (30); the upper needle shaft (52) is in contact with an electrical connection contact point on the circuit board of the device being used; and a spring (54) is provided in the needle tube (51) between the upper needle shaft (52) and the lower needle shaft (53).

2. The pressure sensor based on spring pin electrical connection as claimed in claim 1, characterized in that: The middle part of the outer wall of the needle tube (51) is provided with an annular boss (55); the plug hole (41) is a stepped hole with a smaller top and a larger bottom; the upper plane of the annular boss (55) abuts against the stepped surface of the plug hole (41) to limit the upward movement of the spring needle (50).

3. The pressure sensor based on spring pin electrical connection as claimed in claim 2, characterized in that: The contact surfaces of the upper needle shaft (52), the lower needle shaft (53) and the spring (54) are all inclined surfaces.

4. The pressure sensor based on spring pin electrical connection as claimed in claim 1, characterized in that: The invention comprises a shell (60), wherein the shell (60) comprises an inner cavity extending along the length direction of the shell (60) and being open at both ends; a support ring (20) assembled with a PCB circuit board (30) and a sensor element (10) is installed in the inner cavity of the shell (60); and a fixed frame (40) is located in the inner cavity of the shell (60) above the PCB circuit board (30).

5. The pressure sensor based on spring pin electrical connection as claimed in claim 4, characterized in that: The side walls of the sensor element (10) are respectively provided with a first step (12) and a second step (13); the lower circumferential end of the housing (60) is pressed against the first step (12) and fixed to the first step (12); the lower circumferential end of the support ring (20) is pressed against the second step (13) and fixed to the second step (13).

6. The pressure sensor based on spring pin electrical connection as claimed in claim 5, characterized in that: The fixed frame (40) has a boss on its middle outer wall, the upper peripheral wall of the housing (60) is bent inwardly and pressed against the boss, and the bottom of the side of the fixed frame (40) has a hook (42) supported on the bottom surface of the upper layer of the PCB circuit board (30).

7. The pressure sensor based on spring pin electrical connection as claimed in claim 1, characterized in that: The PCB circuit board (30) is electrically connected to the silicon-based strain gauge (11) via five aluminum wires (70).

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