Pressure sensor and manufacturing method

Abstract

The invention relates to a pressure sensor, and relates to the technical field of pressure sensors, and the pressure sensor comprises a housing defining a mounting cavity, a pressure measurement assembly, a sealing ring, a first pressing part formed by extending from a pressure interface to the interior of the mounting cavity, and a glue injection channel, and the housing comprises an end button and a pressure interface which are combined up and down. One end of the inner side of the pressure leading-in channel is communicated to the mounting cavity; the pressure measuring assembly is arranged in the mounting cavity and comprises a substrate and a pressure sensitive element fixed on the upper side surface or the lower side surface of the substrate; the sealing ring is pressed downwards by the substrate to the pressure interface, the sealing ring, the lower side of the substrate and the pressure interface are enclosed to form a pressure cavity located on the inner side of the sealing ring and a filling cavity located on the outer side of the sealing ring, and the pressure sensitive element is communicated to the pressure cavity; the first pressing part applies pressing force to the first sealing ring through the substrate; and the glue injection channel is used for injecting sealant into the filling cavity. The sealing structure has the effect of being good in sealing performance.

Description

Technical Field

[0001] The present application relates to the technical field of pressure sensors, and in particular to a pressure sensor and a manufacturing method thereof. Background Art

[0002] A pressure sensor is a device that can convert a pressure signal into a measurable electrical signal. It is widely used in various industrial and scientific research fields to monitor and control pressure. The pressure sensor can detect the pressure exerted on the sensor by gas, liquid or solid, and convert it into an electrical signal output such as voltage, current or frequency. According to different test pressure types, pressure sensors can be divided into gauge pressure sensors, differential pressure sensors and absolute pressure sensors.

[0003] The pressure sensor usually includes a pressure interface with a pressure introduction channel. The pressure interface is used to connect to the container of the pressure medium to be measured. The pressure measurement component needs to be sealed to the inner end of the pressure introduction channel to prevent the pressure medium to be measured from leaking into the interior of the pressure sensor. There are two sealing methods between the pressure measurement component and the pressure interface, one is sealing by adhesive bonding, and the other is pressure sealing by a sealing ring. The sealing performance of the pressure sensor using the above sealing method still has room for improvement. Summary of the invention

[0004] The purpose of the present application is to provide a pressure sensor and a manufacturing method, which can further improve the sealing of the pressure sensor to ensure the measurement accuracy of the pressure sensor.

[0005] In a first aspect, a pressure sensor provided by the present application adopts the following technical solution:

[0006] A pressure sensor, comprising: a housing enclosing a mounting cavity, a pressure measuring assembly, a sealing ring, a first pressing portion and a glue injection channel formed by a pressure interface extending into the mounting cavity, the housing comprising a terminal button and a pressure interface assembled in an upper and lower manner, the pressure interface defining a pressure introduction channel having an inner end connected to the mounting cavity;

[0007] The pressure measuring component is arranged in the installation cavity, including a substrate and a pressure sensitive element fixed to the upper surface or the lower surface of the substrate; the sealing ring is pressed downward to the pressure interface by the substrate, and it is enclosed with the lower side of the substrate and the pressure interface to form a pressure cavity located on the inner side of the sealing ring and a filling cavity located on the outer side of the sealing ring, and the pressure sensitive element is connected to the pressure cavity; the first pressing part applies a pressing force to the first sealing ring through the substrate; the glue injection channel is used to inject sealant into the filling cavity.

[0008] By adopting the above technical solution, the injection channel injects sealant into the filling cavity to form a double seal with the sealing ring; further, the first clamping part is riveted to the pressure measuring component to prevent the cured sealant and the sealing ring from loosening. The double sealing process is combined with the riveting process, so that the pressure sensor has better sealing performance and ensures measurement accuracy.

[0009] Optionally, the first pressing part is directly pressed on the substrate, and the glue injection channel includes a hole or a notch arranged on the edge of the substrate, and the lower end of the hole or the notch is connected to the filling cavity; the first pressing part is provided with a yielding part that exposes the hole or the notch upward.

[0010] By adopting the above technical solution, the first pressing part provides a pressing effect and at the same time provides a clearance part for the sealant to pass through, so that the sealant can pass through the first pressing part and the substrate in sequence and then enter the filling cavity to achieve sealed filling.

[0011] Optionally, the first pressing portion is directly pressed onto the substrate, and the glue injection channel includes a hole or a notch provided on the first pressing portion, and the lower end of the hole or the notch is connected to the filling cavity.

[0012] By adopting the above technical solution, the sealant passes through the first pressing part and enters the filling cavity.

[0013] Optionally, it further includes a pressure seat arranged on the substrate, with the first pressing portion facing downward, and indirectly applying a pressing force to the edge of the substrate through the pressure seat.

[0014] By adopting the above technical solution, the pressure seat can better fix the pressure measurement component and provide installation space for the pressure sensor; further, the first clamping part is riveted to the pressure seat, so that the first clamping part and the substrate are separated by the pressure seat, thereby improving the protection effect of the pressure measurement component.

[0015] Optionally, the glue injection channel includes a hole or a notch arranged on the pressure seat.

[0016] By adopting the above technical solution, glue is injected into the filling cavity through the glue injection channel on the pressure seat.

[0017] Optionally, the upper edge of the hole or the notch is provided with an upwardly protruding dam or a sunken surrounding wall.

[0018] By adopting the above technical solution, the setting of the surrounding wall or dam can prevent the sealant from overflowing onto the pressure measuring component when injecting glue from the feed port of the injection channel, thereby providing better protection for the pressure measuring component and ensuring that the pressure measuring component can operate normally after the sealing action is performed.

[0019] Optionally, the pressure seat is provided with a plurality of retaining holes, each of which retains a spring terminal, and the pressure measurement assembly further comprises a processing circuit disposed on the upper side of the substrate and electrically connected to the pressure sensitive element;

[0020] The lower end of the spring terminal is electrically connected to the processing circuit in an electrical contact manner, and the upper end of the spring terminal passes through the pressing seat upward to lead out the electrical signal processed by the processing circuit.

[0021] By adopting the above technical solution, the pressure measurement component leads the signal out of the pressure sensor through the spring terminal, and the retaining hole on the pressure seat can preliminarily fix the spring terminal.

[0022] Optionally, the pressure interface is provided with a boss or annular groove surrounding one inner end of the pressure introduction channel; the inner side of the compressed sealing ring is supported on the outer wall of the boss which is the inner wall of the annular groove facing radially outward.

[0023] By adopting the above technical solution, the sealing ring can be positioned in the form of a ring groove or a boss, preventing the sealing ring from moving, and ensuring that the sealing ring is installed in place.

[0024] Optionally, the outer edge of the upper end of the pressure interface extends upward to form a cylinder, and the upper end of the cylinder forms a second pressing portion for pressing the terminal button downward to the pressure port.

[0025] By adopting the above technical solution, the second pressing portion is riveted onto the terminal button, so that the terminal button is connected to the pressure interface.

[0026] In a second aspect, the present application provides a method for manufacturing a pressure sensor using the following technical solution:

[0027] S1. Provide a pressure interface having a pressure introduction channel, wherein the pressure interface is provided with a cylinder surrounding an inner end of the pressure introduction channel;

[0028] S2, positioning a sealing ring around one end of the inner side of the pressure introduction channel;

[0029] S3, providing a pressure measurement assembly, the pressure measurement assembly comprising a substrate, a processing circuit and a pressure sensitive element disposed on the substrate, and covering the substrate onto the sealing ring;

[0030] S4, pressing the upper end of the cylinder downward to form a first pressing portion to press the substrate and the sealing ring downward, and making the substrate and the pressure interface enclose a pressure cavity located inside the sealing ring and a filling cavity located outside the sealing ring;

[0031] S5, injecting sealant into the filling cavity through a glue injection channel formed on the first pressing part or on the substrate or between the two and connected to the filling cavity, and solidifying the sealant;

[0032] S6. Install a terminal with a terminal onto the pressure interface, and, at the same time or before, electrically connect the terminal to the processing circuit.

[0033] By adopting the above technical solution, the pressure sensor produced has better sealing performance and the measurement accuracy is guaranteed.

[0034] In summary, the present application includes at least one of the following beneficial technical effects:

[0035] 1. In this application, the sealing ring pressed to the pressure interface performs primary sealing on the installation cavity; the sealing ring, the substrate, and the pressure interface are enclosed to form a filling cavity located on the outside, and a sealant is injected into the filling cavity to form a double seal with the sealing ring;

[0036] Furthermore, the first pressing part presses the substrate to prevent the cured sealant and the sealing ring from loosening. The double sealing process is combined with the riveting process to make the pressure sensor have better sealing performance and ensure measurement accuracy.

[0037] 2. In the present application, a pressure seat is provided, and the pressure seat positively presses and fixes the pressure measuring component along the circumferential direction to improve the fixing effect; further, the first clamping part is riveted on the pressure seat, and the pressure seat is used to separate the first clamping part and the substrate, thereby improving the protection effect of the pressure measuring component.

[0038] 3. In addition to being opened on the first clamping part or on the substrate, the glue injection channel in the present application can also be opened on the pressure seat, and a glue collecting structure (i.e., a surrounding wall or a dam) is provided at the feed port of the glue injection channel to prevent the sealant from splashing onto the circuit board and damaging the circuit board when the sealant is poured.

[0039] 4. A retaining hole is provided on the pressure seat in the present application, which can initially limit the spring terminal, thereby facilitating the installation of the spring terminal and allowing the pressure signal to be smoothly led out to the outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic cross-sectional structural diagram of the pressure sensor in this application;

[0041] Figure 2 yes Figure 1 A partial enlarged schematic diagram of part A;

[0042] Figure 3 It is a partial structural schematic diagram of the present application when the glue injection channel is opened in the first pressing part;

[0043] FIG. 4 is a schematic diagram of the local structure when the glue injection channel is opened at other positions in the present application.

[0044] In the figure, 1. shell; 11. terminal; 111. through hole; 12. pressure interface; 121. pressure introduction channel; 122. boss; 2. mounting cavity; 21. pressure cavity; 22. filling cavity; 3. pressure measurement component; 31. substrate; 311. pressure through hole; 32. processing circuit; 33. pressure sensitive element; 4. sealing ring; 5. first clamping part; 50. yielding part; 51. vertical section; 52. horizontal section; 53. clamping section; 6. glue injection channel; 7. pressure seat; 71. mating surface; 72. retaining hole; 8. spring terminal; 9. second clamping part; 10. sealant; 20. glue collection structure; 30. connecting part. DETAILED DESCRIPTION

[0045] The following will be combined with the attached Figure 1 -4 clearly and completely describes the technical solution of the present application. The following embodiments are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application. In the following description, the same mark is used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0046] In the description of the present application, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present application are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0047] In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0048] It should be further understood that the term “and / or” used in the specification and corresponding claims of this application refers to any and all possible combinations of one or more of the listed items.

[0049] Embodiment 1:

[0050] A pressure sensor, referring to Figure 1 and Figure 2, comprising a housing 1 and a pressure measuring assembly 3. The housing 1 comprises a terminal 11 and a pressure interface 12 which are combined in an upper and lower manner, and the terminal 11 and the upper end surface of the pressure interface 12 enclose an installation cavity 2. The pressure interface 12 defines a pressure introduction channel 121 whose inner end is connected to the installation cavity 2.

[0051] The pressure measurement assembly 3 is disposed in the installation cavity 2 , and may include a substrate 31 , a processing circuit 32 (preferably a circuit board) and a pressure sensitive element 33 fixed to the upper surface or the lower surface of the substrate 31 .

[0052] In this embodiment, the pressure sensitive element 33 is specifically fixed to the upper surface of the substrate 31. The substrate 31 is provided with a pressure through hole 311 (not marked) connected to the pressure chamber 21, and the pressure sensitive element 33 blocks the upper end of the pressure through hole 311.

[0053] Furthermore, the processing circuit 32 may be located on the upper surface of the substrate 31, and the processing circuit 32 is electrically connected to the pressure sensitive element 33. After the medium enters the mounting cavity 2 from the pressure introduction channel 121, the pressure sensitive element 33 senses the pressure of the medium entering the pressure cavity 21 to form a pressure signal, and then the processing circuit 32 converts the pressure signal into an electrical signal, thereby measuring the pressure of the medium.

[0054] Among them, a sealing ring 4 can be arranged between the substrate 31 and the pressure interface 12, and the sealing ring 4 is pressed downward by the substrate 31 to the upper end face of the pressure interface 12, and surrounds the inner end (i.e., the upper end in the figure) of the pressure introduction channel 121. In this embodiment, a first pressing portion 5 is formed on the pressure interface 12 to extend into the installation cavity 2, and the first pressing portion 5 applies a downward pressing force to the first sealing ring 4 through the substrate 31. After the sealing ring 4 is pressed by the first pressing portion 5, the sealing ring 4, the lower side of the substrate 31, and the upper end face of the pressure interface 12 are enclosed to form a pressure cavity 21 located inside the sealing ring 4 and a filling cavity 22 located outside the sealing ring 4, and the filling cavity 22 can be filled with a sealant 10. Among them, the pressure interface 12 can be made of metal material.

[0055] Specifically, in this embodiment, the first pressing part 5 can be riveted on the substrate 31, thereby indirectly providing the above-mentioned downward pressing force to the sealing ring 4 through the substrate 31. The first pressing part 5 presses the substrate 31, so that the sealing ring 4 can play a better sealing role to prevent the medium from flowing out of the installation cavity 2. The medium passes through the pressure introduction channel 121 and enters the pressure cavity 21, and the pressure measurement component 3 measures the pressure of the medium. The filling cavity 22 can be filled with sealant 10, and the sealant 10 and the sealing ring 4 are combined to form a double seal.

[0056] In addition, in order to better position the sealing ring 4 and make the sealing ring 4 have a higher installation accuracy, the pressure interface 12 may be provided with a boss 122 or an annular groove around the inner end of the pressure introduction channel 121. In this embodiment, the pressure interface 12 is preferably provided with a boss 122, and the inner side of the compressed sealing ring 4 is supported on the outer wall of the boss 122, so as to position the sealing ring 4.

[0057] It should be noted that, in other embodiments, an annular groove may also be provided on the pressure interface 12 , and in this case, the outer wall of the compressed sealing ring 4 is supported on the annular wall of the annular groove.

[0058] Furthermore, a pressure seat 7 is provided on the substrate 31. The first pressing portion 5 faces downward, and the above-mentioned pressing force is indirectly applied to the edge of the substrate 31 through the pressure seat 7. After the sealing ring 4 and the pressure measuring component 3 are positioned and installed around one end of the inner side of the pressure introduction channel 121 in sequence, the pressure seat 7 is pressed on the substrate 31 to further fix the substrate 31. The first pressing portion 5 is riveted on the pressure seat 7, and the first pressing portion 5 and the pressure seat 7 are separated by the pressure seat 7, so that the pressure measuring component 3 is better protected. At the same time, the risk of the first pressing portion 5 made of metal being directly pressed on the upper side of the substrate 31 and causing a short circuit with the processing circuit 32 can be avoided.

[0059] It should be noted that, in the present embodiment, the first pressing portion 5 is a vertical cylinder before being pressed, and one end of the cylinder away from the pressure interface 12 is pressed downward to form the first pressing portion 5 .

[0060] Furthermore, a mating surface 71 (specifically a conical surface) is provided at one end of the press seat 7 facing away from the substrate 31, and the mating surface 71 is provided along the outer edge of the press seat 7. The first pressing portion 5 is riveted on the wall surface of the mating surface 71, so that the first pressing portion 5 does not need to be bent at an excessive angle, and can also be well fitted with the press seat 7, thereby ensuring the sealing performance of the sensor.

[0061] Correspondingly, in this embodiment, a glue injection channel 6 is provided on the press seat 7, and the glue injection channel 6 is arranged in a winding manner and communicated with the filling cavity 22. The sealant 10 is poured into the filling cavity 22 through the feed port of the glue injection channel 6. Furthermore, a glue collecting structure 20 is provided at the feed port of the glue injection channel 6, and the glue collecting structure 20 can prevent the sealant 10 from splashing onto the circuit board when pouring the sealant 10.

[0062] It should be noted that the injection channel 6 can be in various forms (such as holes, such as notches). The present application does not impose any specific restrictions on the form of the injection channel 6. It is only necessary to ensure that the injection channel 6 can be connected to the filling cavity 22 so that the sealant 10 can be smoothly poured into the filling cavity 22.

[0063] The glue collecting structure 20 can be a wall, a dam or other forms. For example, the feed port of the glue injection channel 6 is recessed toward the pressure interface 12 to form a wall around it, or the feed port of the glue injection channel 6 extends toward the end button 11 to form a circle of dam.

[0064] In this embodiment, the glue collecting structure 20 is in the form of a surrounding wall.

[0065] In addition, refer to Figure 1 and Figure 2 The press seat 7 may also be provided with a holding hole 72, and a plurality of holding holes 72 are provided, and a spring terminal 8 is held in each of the plurality of holding holes 72; specifically, the spring terminal 8 may include a large diameter portion and a small diameter portion, and the large neck portion and the small diameter portion are integrally formed. The large neck portion is arranged toward the circuit board, and both ends of the large diameter portion have a conical surface; one end of the spring terminal 8 is electrically connected to the circuit board in an electrically contacting manner, and the other end of the spring terminal 8 passes through the press seat 7 to lead the electrical signal processed by the circuit board outward.

[0066] A through hole 111 is provided on the terminal button 11 for the spring terminal 8 to pass through. The cross-section of the through hole 111 is conical, and the conical surface at the large diameter end of the spring terminal 8 fits tightly with the conical surface at the through hole 111, thereby limiting the spring terminal 8 and preventing the spring terminal 8 from deflecting.

[0067] After the sealing ring 4, the pressure measuring assembly 3 and the pressure seat 7 are installed in place, the spring terminal 8 is inserted into the retaining hole 72 and connected to the processing circuit 32, and the retaining hole 72 performs preliminary positioning of the spring terminal 8. At this time, the through hole 111 on the terminal button 11 is aligned with the spring terminal 8, so that the small diameter portion of the spring terminal 8 passes through the through hole 111, and a conical surface of the large diameter portion of the spring terminal 8 (located at the waist of the spring terminal 8) is tightly fitted with the wall surface of the through hole 111, so that it is retained in the retaining hole 72.

[0068] It should be noted that in some other embodiments, the spring terminal 8 may not pass through the terminal button 11. Specifically, a pin is fixed on the terminal button 11, and another circuit board is provided on one side of the terminal button 11 close to the substrate 31; the pin passes through the terminal button 11 and is soldered to one side of the circuit board, while the spring terminal 8 forms an electrical contact with the other side of the circuit board.

[0069] In addition, in this embodiment, the end button 11 is fixedly connected to the pressure interface 12 by riveting. Specifically, a cylinder is further provided on the pressure interface 12. When the end button 11 is engaged with the pressure interface 12, the upper end of the cylinder is pressed downward to form a second pressing portion 9 riveted to the end button 11.

[0070] In this embodiment, the two cylinders forming the first pressing part 5 and the second pressing part 9 can be integrally formed. Figure 1 A connecting portion 30 in the shape of an annular plate is provided between the first pressing portion 5 and the second pressing portion 9. The connecting portion 30 is fixed to the pressure interface 12, the inner ring of the connecting portion 30 is connected to the first pressing portion 5, and the outer ring of the connecting portion 30 is connected to the second pressing portion 9. The connecting portion 30 can be welded to the upper end surface of the metal pressure interface 12, or molded in the plastic pressure interface 12.

[0071] In other embodiments, the two cylinders forming the first pressing part 5 and the second pressing part 9 can be separately provided, that is, the two cylinders are respectively connected to the pressure interface 12 in one piece. The present application does not specifically limit the specific forms of the first pressing part 5 and the second pressing part 9, as long as they can play the riveting role.

[0072] In addition, this embodiment also discloses a method for manufacturing a pressure sensor, comprising the following steps:

[0073] S1. Provide a pressure interface 12 having a pressure introduction channel 121, wherein the pressure interface 12 is provided with a cylinder surrounding an inner end of the pressure introduction channel 121;

[0074] S2, positioning a sealing ring 4 around one end of the inner side of the pressure introduction channel 121;

[0075] S3, providing a pressure measurement assembly 3, the pressure measurement assembly 3 comprising a substrate 31, a processing circuit 32 and a pressure sensitive element 33 disposed on the substrate 31, and covering the substrate 31 on the sealing ring 4;

[0076] S4, pressing the upper end of the cylinder downward to form a first pressing portion 5 to press the substrate 31 and the sealing ring 4 downward, and making the substrate 31 and the pressure interface 12 enclose a pressure chamber 21 located inside the sealing ring 4 and a filling chamber 22 located outside the sealing ring 4;

[0077] S5, injecting the sealant 10 into the filling cavity 22 through a glue injection channel 6 formed on the first pressing portion 5 or on the substrate 31 or between the two and connected to the filling cavity 22, and curing the sealant 10;

[0078] S6. Install a terminal 11 with a terminal onto the pressure interface 12, and, at the same time or before, electrically connect the terminal to the processing circuit 32.

[0079] In this embodiment, the installation cavity 2 is sealed at the primary level by means of the sealing ring 4 which is pressed onto the pressure interface 12. The pressed sealing ring 4 is enclosed with the lower side of the substrate 31 and the pressure interface 12 to form a pressure cavity 21 located inside the sealing ring 4 and a filling cavity 22 located outside the sealing ring 4. The sealing glue 10 can be injected into the filling cavity 22 through the injection channel 6, so that the sealing glue 10 and the sealing ring 4 form a double seal.

[0080] Furthermore, the first pressing portion 5 presses the substrate 31. The setting of the first pressing portion 5 prevents the cured sealant 10 and the sealing ring 4 from loosening. The double sealing process is combined with the riveting process, so that the pressure sensor has better sealing performance and ensures measurement accuracy.

[0081] Embodiment 2:

[0082] Reference Figure 3 The difference between this embodiment and the first embodiment is that the opening position of the glue injection channel 6 is different. In this embodiment, the glue injection channel 6 is opened on the first pressing part 5, and the specific form of the first pressing part 5 is adjusted.

[0083] The first pressing part 5 includes a vertical section 51, a transverse section 52 and a pressing section 53 connected in sequence. The vertical section 51 is connected to the pressure interface 12; the pressing section 53 is inclined and pressed on the inclined surface of the matching surface 71; and the glue injection channel 6 is vertically opened on the transverse section 52.

[0084] When the cylinder is forming the first pressing portion 5, a glue injection channel 6 is firstly opened on the end of the cylinder, and then the end of the cylinder is bent twice to form a vertical section 51, a transverse section 52 and a pressing section 53 which are connected in sequence.

[0085] This embodiment adjusts the shape of the first clamping portion 5 to prevent the pressure seat 7 from blocking the glue injection channel 6 when the glue injection channel 6 is opened on the first clamping portion 5, so that the sealant 10 can enter the filling cavity 22 from the glue injection channel 6 on the first clamping portion 5.

[0086] Embodiment 3:

[0087] Referring to Figure 4, the difference between this embodiment and the above embodiment is that the setting of the pressure seat 7 is cancelled. The first pressing portion 5 is directly pressed on the substrate 31, and the first pressing portion 5 includes a vertical section 51 and a transverse section 52. Correspondingly, the glue injection channel 6 is opened on the substrate 31 or the first pressing portion 5. Three forms of opening the glue injection channel 6 are listed in this embodiment. It should be noted that the form of the glue injection channel 6 is not limited to the above three types, and all adaptive adjustments of the glue injection channel 6 should be covered within the protection scope of this application.

[0088] Reference Figure 4a At this time, the injection channel 6 is opened at the edge of the substrate 31, and a clearance portion 50 is provided on the first pressing portion 5, and the clearance portion 50 avoids the feed port of the injection channel 6. When the glue is injected, the sealant 10 passes through the clearance portion 50 and the injection channel 6 in sequence and enters the filling cavity 22.

[0089] Further, refer to Figure 4b and Figure 4c , at this time, the glue injection channel 6 is opened on the first pressing part 5. When the edge of the substrate 31 abuts against the vertical section 51, the glue injection channel 6 adopts Figure 4b The glue injection channel 6 is arranged in a winding manner; when the edge of the substrate 31 and the vertical section 51 are in clearance, the glue injection channel 6 is adopted Figure 4c in the form of, that is, the glue injection channel 6 is directly vertically opened on the transverse section 52.

[0090] This embodiment makes the assembly of the pressure sensor more simplified by eliminating the pressure seat 7. When the sealant 10 is filled into the filling cavity 22, it can be filled through the injection channel 6 opened on the first pressing part 5 or the base plate 31.

[0091] The embodiments of this specific implementation are all preferred embodiments of this application, and are not intended to limit the protection scope of this application. The same components are represented by the same figure marks. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the protection scope of this application.

Claims

1. A pressure sensor, characterized in that: include: A housing (1) enclosing a mounting cavity (2) comprises a terminal button (11) and a pressure interface (12) which are combined in an upper and lower manner, wherein the pressure interface (12) defines a pressure introduction channel (121) whose inner end is connected to the mounting cavity (2); A pressure measurement assembly (3) is arranged in the installation cavity (2), comprising a substrate (31) and a pressure sensitive element (33) fixed to the upper surface or the lower surface of the substrate (31); The sealing ring (4) is pressed downwardly by the substrate (31) to the pressure interface (12), and is enclosed with the lower side of the substrate (31) and the pressure interface (12) to form a pressure chamber (21) located inside the sealing ring (4) and a filling chamber (22) located outside the sealing ring (4), and the pressure sensitive element (33) is connected to the pressure chamber (21); A first pressing portion (5) extending from the pressure interface (12) into the installation cavity (2) and applying a pressing force to the first sealing ring (4) via the base plate (31); and a glue injection channel (6) for injecting a sealing glue (10) into the filling cavity (22).

2. A pressure sensor according to claim 1, characterized in that: The first pressing portion (5) is directly pressed onto the substrate (31); the glue injection channel (6) comprises a hole or a notch arranged at the edge of the substrate (31); the lower end of the hole or the notch is connected to the filling cavity (22); and the first pressing portion (5) is provided with a yielding portion (50) for exposing the hole or the notch upward.

3. A pressure sensor according to claim 1, characterized in that: The first pressing portion (5) is directly pressed onto the substrate (31), and the glue injection channel (6) comprises a hole or a notch provided on the first pressing portion (5), and the lower end of the hole or the notch is connected to the filling cavity (22).

4. A pressure sensor according to claim 1, characterized in that: It also comprises a pressure seat (7) arranged on the base plate (31), wherein the first pressing portion (5) faces downward and indirectly applies a pressing force to the edge of the base plate (31) via the pressure seat (7).

5. A pressure sensor according to claim 4, characterized in that: The glue injection channel (6) comprises a hole or a notch arranged on the pressure seat (7).

6. A pressure sensor according to claim 5, characterized in that The upper edge of the hole or the notch is provided with a dam protruding upward or a surrounding wall formed by sinking.

7. A pressure sensor according to claim 4 or 5, characterized in that: The pressure seat (7) is provided with a plurality of retaining holes (72), each of which retains a spring terminal (8). The pressure measuring assembly (3) further comprises a processing circuit (32) which is arranged on the upper side of the substrate (31) and is electrically connected to the pressure sensitive element (33); The lower end of the spring terminal (8) is electrically connected to the processing circuit (32) in an electrical contact manner, and the upper end of the spring terminal (8) passes through the pressure seat (7) upward to lead out the electrical signal processed by the processing circuit (32).

8. A pressure sensor according to claims 1-7, characterized in that: The pressure interface (12) is provided with a boss (122) or an annular groove surrounding one end of the inner side of the pressure introduction channel (121); the inner side of the compressed sealing ring (4) is supported on the outer wall of the boss (122) which is the inner wall of the annular groove facing radially outward.

9. A pressure sensor according to any one of claims 1 to 7, characterized in that: The outer edge of the upper end of the pressure interface (12) extends upward to form a cylinder, and the upper end of the cylinder forms the second pressing portion (9) for pressing the terminal button (11) downward to the pressure port.

10. A method for manufacturing a pressure sensor, characterized in that: The following steps are involved: S1. Providing a pressure interface (12) having a pressure introduction channel (121), wherein the pressure interface (12) is provided with a cylinder surrounding an inner end of the pressure introduction channel (121); S2, positioning a sealing ring (4) around one end of the inner side of the pressure introduction channel (121); S3, providing a pressure measurement assembly (3), the pressure measurement assembly (3) comprising a substrate (31), a processing circuit (32) and a pressure sensitive element (33) disposed on the substrate (31), and covering the substrate (31) on the sealing ring (4); S4, pressing the upper end of the cylinder downward to form a first pressing portion (5) to press the base plate (31) and the sealing ring (4) downward, and making the base plate (31) and the pressure interface (12) enclose a pressure chamber (21) located inside the sealing ring (4) and a filling chamber (22) located outside the sealing ring (4); S5, injecting a sealant (10) into the filling cavity (22) through a sealant injection channel (6) formed on the first pressing portion (5) or on the base plate (31) or between the two and connected to the filling cavity (22), and solidifying the sealant (10); S6. Install a terminal (11) with a terminal onto the pressure interface (12), and, at the same time or before, electrically connect the terminal to the processing circuit (32).

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