Pressure sensor

Abstract

The utility model provides a pressure sensor, and the sensor comprises a first housing which comprises a first pipe body with a first port, and a second port communicated with an inner cavity of the first housing; the second shell comprises a second pipe body, one end of the second pipe body is hermetically connected to the second port, and the other end of the second pipe body is coupled to the pressure measuring assembly. According to the pressure sensor, only the first shell needs to be replaced for different mounting interface specifications, so that the universality is improved, and the cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a pressure sensor. Background Art

[0002] The pressure sensor usually has at least one pressure interface to receive the fluid to be measured. The pressure interface is mechanically mounted and sealed to the container holding the fluid to be measured. For different mounting interfaces of the holding container, pressure interfaces of different specifications are required for adaptation. This results in the housing of the pressure sensor needing to be adapted to each different mounting interface, so the versatility is poor, which pushes up the manufacturing cost. Utility Model Content

[0003] In view of the deficiencies of the prior art, the present application provides a pressure sensor to improve the adaptability to different installation interfaces.

[0004] To achieve the above objectives, the present application provides a pressure sensor, comprising:

[0005] A first housing, comprising a first tube having a first port and a second port connected to an inner cavity of the first housing;

[0006] A second shell body having an inner cavity provided with a pressure measuring assembly includes a second tube body having one end sealedly connected to the second port and the other end coupled to the pressure measuring assembly.

[0007] For the pressure sensor described above, only the first housing needs to be replaced for different installation interface specifications, thereby improving versatility and reducing costs.

[0008] Preferably, the second shell is fixedly connected to the first shell via a snap-fit ​​structure.

[0009] Preferably, at least one buckle is formed on the upper part of the second shell, and the buckle includes an extension portion formed by extending upward from the upper end of the first tube body and a claw formed by protruding from the upper end of the extension portion toward the side wall of the second shell, and the claw is locked downward on a stop portion formed by protruding outward from the outer wall of the second shell.

[0010] Preferably, a window is formed in the middle of the extension portion, and the catch faces downward close to the upper edge of the window.

[0011] Preferably, at least one buckle is formed on the second shell, and the buckle includes an extension portion formed by extending upward from the upper end of the first tube body, a window is formed in the middle of the extension portion, and the upper edge of the window is locked downward on a stop portion formed by protruding outward from the outer wall of the second shell.

[0012] Preferably, a sealing groove is formed on the outer wall of the second tube body, a first sealing ring is arranged in the sealing groove, and the first sealing ring is sealedly connected to the second port.

[0013] Preferably, the pressure measuring component is sealingly connected to the inner cavity of the second tube body through a second sealing ring.

[0014] Preferably, the pressure sensor also includes a third tube body having one end sealed and fixed to the outside of the first tube body, a valve cavity is formed between the third tube body and the outer wall of the first tube body, the valve cavity is respectively connected to the inner cavity of the first tube body and the inner cavity of the third tube body, and a valve plate is provided in the valve cavity for allowing only one-way flow of fluid from the inner cavity of the first tube body to the inner cavity of the third tube body.

[0015] Preferably, an annular plate is formed at one end of the third tube body close to the tube body, the outer wall of the first tube body protrudes outward to form a ring-shaped portion, a ring groove is formed on the outer end surface of the ring-shaped portion, and the plate protrudes toward the side of the first tube body to form an outer cylinder, which extends into the ring groove and is bonded and sealed with the ring groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a three-dimensional schematic diagram of a pressure sensor of a preferred embodiment;

[0017] Figure 2 A top view of a pressure sensor according to a preferred embodiment;

[0018] Figure 3 The pressure sensor of the preferred embodiment is Figure 2 A cross-sectional view of AA is shown;

[0019] Figure 4 is a cross-sectional view of a pressure measurement assembly of a preferred embodiment;

[0020] Description of reference numerals: 101, annular portion; 10b, annular groove; 10, positioning column; 11a, port; 11, tube body; 120, adhesive; 121, outer tube; 122, connecting plate; 123, inner tube; 124, plate; 125, flow gap; 12a, port; 12, tube body; 13a, port; 13, upper end; 14a, extension portion; 14b, buckle claw; 14c, window; 14, buckle; 15, guide portion; 16, valve plate; 1a, through hole; 1b, outer surface; 1, shell; 201, sealing ring; 20a, sealing ring; 20b, pressure through hole; 20, tube body; 210, positioning portion; 211, hot riveting column; 212, cavity; 21a, stopper; 21b, side positioning portion; 21, lower shell; 22a, gap; 22b, adhesive; 22, upper shell; 231, other end; 23a, electrical connection pin; 23b, electrical connection pin; 23, electrical connection plug; 24a, waterproof breathable membrane; 24, breather hole; 2, shell; 31a, upper surface; 31b, lower surface; 31c, pressure via; 31, substrate; 320, pressure sensitive element; 321, step hole; 322, electrical connection line; 32a, metallized hole; 32b, riveted hole; 32c, step surface; 32, circuit board; 33, protective material; 3, pressure measurement component. DETAILED DESCRIPTION

[0021] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. 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 symbols are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] Please refer to Figures 1 to 3 A pressure sensor of a preferred embodiment includes a housing 1 and a housing 2. The housing 1 has at least one tube body 11, and a port 11a is provided at one end of the outer side of the tube body 11. The housing 1 is also provided with a port 13a, and the port 11a and the port 13a are arranged at opposite ends. For example, the housing 1 can extend downward to form the tube body 11, and the port 11a is arranged at the lower end of the tube body 11, and the port 13a is arranged at the upper end of the housing 1. Among them, the port 11a is used to mechanically connect and seal with the mounting port arranged on the container (not shown) containing the fluid (liquid, gas) to be measured. The housing 2 includes a lower shell 21 and an upper shell 22 connected to each other, and the upper shell 22 and the lower shell 21 surround the inner cavity of the housing 2. For example, the upper shell 22 can form a circle of flanges (not shown) downwards, and the flanges are arranged downwards in a circle of sealing grooves formed by an opening edge at the upper end of the lower shell 21, and a gap 22a is formed between the sealing groove and the flange, and the gap 22a is filled with adhesive 22b. The lower end of the upper shell 22 is provided with a downwardly facing tube body 20, which is sealed and inserted into the port 13a of the shell 1. For example, a circle of sealing grooves is formed on the outer wall of the tube body 20, and a sealing ring 20a is provided in the sealing groove. The sealing ring 20a is sealed and connected to the inner wall of the port 13a. A pressure measuring assembly 3 is provided in the inner cavity of the shell 2. The pressure measuring assembly 3 has a pressure sensitive element 320. One sensing surface of the pressure sensitive element is coupled (exposed or connected) to the fluid entering the tube body 20 to measure the pressure of the fluid; the other sensing surface of the pressure sensitive element is coupled to the atmospheric pressure through a downwardly arranged air vent 24, so as to measure the gauge pressure of the fluid to be measured relative to the atmosphere. In some other schemes, preferably, when the other sensing surface of the pressure sensitive element is coupled to a vacuum chamber (for example, surrounded by a vacuum cover or lid and the pressure sensitive element), the absolute pressure of the fluid to be measured can also be measured. The waterproof breathable membrane 24a can be used to prevent water vapor from entering the inner cavity of the housing 2 while being connected to the atmosphere. It is preferably arranged on a mounting plane formed by one end of the inner side of the vent hole 24. The vent hole 24 is staggered with the electrical connection pins 23a, that is, the vent hole 24 passes through a plurality of electrical connection pins 23a. The lower shell 21 expands outward at the root of the tube body 20 to form a positioning portion 210. The lower end outlet surface of the vent hole 24 is located above the lower surface of the positioning portion 210, so that the vent hole 24 is relatively raised to avoid being blocked during installation. Preferably, the port 13a is a bell mouth with a cross section that gradually expands upward, so as to facilitate the insertion of the tube body 20.

[0026] The pressure sensor may also include a tube body 12, which is combinedly connected to the outside of the tube body 11, and a port 12a is provided at one end of the tube body 12 away from the tube body 11. The tube body 12 can be plugged and sealed with a ring-shaped portion 101 formed by the outer wall of the tube body 11 protruding outward. For example, a ring-shaped plate 124 is formed at one end of the tube body 12 close to the tube body 11, and the plate 124 is preferably arranged perpendicular to the tube body 12. The plate 124 protrudes toward one side of the tube body 11 to form a circle of outer cylinder 121. An annular groove 10b is formed on the end surface of the annular portion 101 facing the plate 124. The outer cylinder 121 extends into the annular groove 10b and is connected and sealed by an adhesive 120. Among them, a valve cavity (not marked) is enclosed between the tube body 12 and the outer surface 1b of the tube body 11, and a valve plate 16 is provided in the valve cavity for allowing fluid to flow from the port 11a to the port 12a in one direction. In this way, when a negative pressure source is connected to the port 11a and a negative pressure chamber is connected to the port 12a, the negative pressure in the housing 2 can be measured by pumping negative pressure into the negative pressure chamber.

[0027] The valve plate 16 can be arranged in the valve cavity as follows: the outer surface 1b of the tube body 11 protrudes outward to form a positioning column 10, and at least one through hole 1a is formed on the side wall of the tube body 11 around the positioning column 10 to connect the inner cavity of the housing 1 and the valve cavity. At the same time, the valve cavity is connected with the inner cavity of the tube body 12, and the valve plate 16 is movably sleeved on the positioning column 10, and the maximum displacement of the middle part of the valve plate 16 moving toward the side of the tube body 12 is limited by the protrusion (not marked) formed by the plate 124 extending toward the side of the tube body 11. When the fluid pressure at the port 11a is less than the fluid pressure at the port 12a, the valve plate is attached to the closed support surface (not marked) formed on the outer surface 1b of the tube body 11 toward the side of the tube body 11 to prevent the fluid from flowing from the port 12a to the port 11a. The protrusion may include an inner cylinder 123 and a connecting plate 122 for connecting the inner cylinder 123 with the outer cylinder 121. The connecting plate 122 preferably extends along the radial direction of the tube body 12. A flow gap 125 is provided between the inner cylinder 123 and the outer cylinder 121 to connect the valve cavity and the inner cavity of the tube body 12. The positioning column 10 may be inserted into the inner cylinder 123 to help position the tube body 11 and the tube body 12.

[0028] Please refer to Figure 4In a preferred embodiment, the pressure measuring assembly 3 may include a pressure sensitive element 320 for measuring the pressure of the fluid to be measured in the inner cavity of the housing 1. The pressure sensitive element 320 may be a semiconductor pressure sensitive element, which has a semiconductor film, the edge of which is supported by a circle of base, and the base is fixedly and sealedly connected to the upper surface 31a of the substrate 31, the lower surface 31b of the substrate 31 faces the side of the housing 1, and a sealing ring 201 is squeezed and sealed to the bottom of a concave cavity 212 formed on the lower shell 21, and the bottom of the concave cavity 212 is connected to the inner cavity of the tube body 20 through a pressure through hole 20b, thereby connecting the inner cavities of the housing 1. The substrate 31 is provided with a pressure through hole 31c, and the pressure through hole 31c and the pressure through hole 20b are both located inside the sealing ring 201, and the lower end of the pressure through hole 31c and the upper end of the pressure through hole 20b are connected through the height space supported by the sealing ring 201 between the substrate 31 and the lower shell 21. The pressure measurement assembly 3 further includes a circuit board 32 that is fixed to the pressure measurement assembly 3. The circuit board 32 has a step hole 321. The step hole 321 has a step surface 32c facing upward. The step surface 32c is provided with a conductive trace (not shown). The pressure sensitive element 320 is located in the step hole 321 and is electrically connected to the conductive trace on the step surface 32c through a plurality of electrical connection lines 322, thereby being electrically connected to the circuit board 32. In order to protect the electrical connection lines 322, silicone gel can be filled in the step hole 321 as a protective material 33 to cover the pressure sensitive element 320 and the electrical connection lines 322. In addition to setting the pressure sensitive element 320 in the step hole 321, some other electronic components can also be set in the step hole 321 and protected by the protective material 33, such as a signal processing chip. Other electronic components, such as resistors, capacitors, etc., can also be set on the upper surface of the circuit board 32.

[0029] In order to enable the substrate 31 to squeeze the sealing ring 201 with a certain pressure, a plurality of metallized holes 32a and a plurality of riveting holes 32b can be provided on the circuit board 32, wherein a plurality of electrical connection pins 23a, 23b embedded in the lower shell 21 can form a fish eye at one end and insert the fish eye into and mechanically and electrically connect with the metallized hole 32a, and at the same time, a hot riveting column 211 formed by the upper protrusion of the lower shell 21 passes upward through the riveting hole 32b and is riveted and fixed to the substrate 31. The other end 231 of the plurality of electrical connection pins 23a extends outward into the interior of a shell-shaped electrical connection plug 23 formed on the side wall of the lower shell 21 to electrically connect with the external device. The metallized hole 32a and the riveting hole 32b are located outside the substrate 31.

[0030] The pressure measurement assembly 3 of this embodiment, by providing a stepped hole 321 on the circuit board 32 to accommodate the protective material 33, can replace the enclosure frame (such as the enclosure frame shown in CN115468686A) used more frequently in the prior art as a retaining component for the protective material 33, avoiding the enclosure frame being fixed to the upper surface of the circuit board 32 by bonding or other means, and can reduce costs to a certain extent in terms of processes and parts. Among them, in this embodiment, the lower surface of the circuit board 32 can be bonded to the upper surface 31a of the substrate 31. The material of the substrate 31 can be a ceramic material (such as alumina) or a metal material (such as stainless steel), so that it can be closer to the thermal expansion coefficient of semiconductor silicon. The base material of the circuit board 32 can also be made of ceramic material. At this time, the part of the electrical connection pin 23a exposed in the inner cavity of the housing 2 can be electrically connected to the pad provided on the circuit board 32 through a metal wire (not shown).

[0031] In some other solutions, the metallized hole 32a, the riveted hole 32b and the sealing ring 201 can be omitted accordingly, and the substrate 31 is sealed and fixed to the flat surface formed at the bottom of the cavity 212 by bonding, and the sealed communication between the substrate 31 and the pressure hole 20b is not achieved by pressure sealing. In this case, the pressure hole 31c is aligned and communicated with the pressure hole 20b, or directly extends and communicates with the inner cavity of the tube body 20.

[0032] The tube body 20 can be tightly fitted with the port 13a directly or through a sealing ring 20a. In some other schemes, alternatively / additionally, the upper end 13 of the housing 1 can be fixed to the lower shell 21 through a buckle structure. For example, two buckles 14 can be formed on two opposite sides of the lower shell 21, and the buckle 14 includes an extension 14a formed by the upper end of the tube body 11 extending upward, and a claw 14b formed by the upper end of the extension 14a protruding toward the side wall of the lower shell 21, and the claw 14b is locked downward on a stopper 21a formed by the outer wall of the lower shell 21 protruding downward. At least one buckle 14 can be provided. Preferably, a window 14c is formed in the middle of the extension 14a, and the claw 14b is downward close to the upper edge of the window 14c. At this time, the claw 14b can be omitted, and the upper edge of the window 14a is directly locked downward on the stopper 21a.

[0033] In some other schemes, preferably, several guide structures can also be provided so that the tube body 20 can be accurately inserted into the port 13a. For example, the upper end 13 of the tube body 11 can be extended upward to form a guide portion 15 in a plate-like or other suitable shape, and correspondingly, side positioning portions 21b located on the left and right sides of the guide portion 15 are formed on the outer side of the underground shell 21.

[0034] The scope of the disclosure is defined not by the detailed description but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are construed as being included in the disclosure.

Claims

1. A pressure sensor, characterized in that: include: A first shell (1) comprises a first tube (11) having a first port (11a) and a second port (13a) connected to the inner cavity of the first shell (1); A second housing (2) having an inner cavity provided with a pressure measuring assembly (3) comprises a second tube (20) having one end sealedly connected to the second port (13a) and the other end coupled to the pressure measuring assembly (3).

2. The pressure sensor according to claim 1, characterized in that: The second shell (2) is fixedly connected to the first shell (1) via a snap-fit ​​structure.

3. The pressure sensor according to claim 2, characterized in that: At least one buckle (14) is formed on the second shell (2), the buckle (14) comprising an extension portion (14a) formed by the upper end of the first tube (11) extending upward, and a buckle claw (14b) formed by the upper end of the extension portion (14a) protruding toward the side wall of the second shell (2), the buckle claw (14b) locking downward on a stopper portion (21a) formed by the outer wall of the second shell (2) protruding outward.

4. The pressure sensor according to claim 3, characterized in that: A window (14c) is formed in the middle of the extension portion (14a), and the catch (14b) faces downward and is close to the upper edge of the window (14c).

5. The pressure sensor according to claim 2, characterized in that: At least one buckle (14) is formed on the upper side of the second shell (2), the buckle (14) comprising an extension portion (14a) formed by extending upward from the upper end of the first tube (11), a window (14c) formed in the middle of the extension portion (14a), and an upper edge of the window (14c) locking downwardly on a stopper portion (21a) formed by protruding outward from the outer wall of the second shell (2).

6. The pressure sensor according to claim 1, characterized in that The second port (13a) and the first port (11a) are located at opposite ends of the first shell (1).

7. The pressure sensor according to any one of claims 1 to 6, characterized in that: The outer wall of the second tube body (20) forms a circle of sealing groove, a first sealing ring (20a) is arranged in the sealing groove, and the first sealing ring (20a) is sealedly connected to the second port (13a).

8. The pressure sensor according to any one of claims 1 to 6, characterized in that The pressure measuring component (3) is sealedly connected to the inner cavity of the second tube body (20) via a second sealing ring (201).

9. The pressure sensor according to any one of claims 1 to 6, characterized in that: The invention also comprises a third tube body (12) having one end sealed and fixed on the outside of the first tube body (11); a valve cavity is formed between the outer wall of the third tube body (12) and the first tube body (11); the valve cavity is connected to the inner cavity of the first tube body (11) and the inner cavity of the third tube body (12) respectively; a valve plate (16) is arranged in the valve cavity for allowing only one-way flow of fluid from the inner cavity of the first tube body (11) to the inner cavity of the third tube body (12).

10. The pressure sensor according to claim 9, characterized in that An annular plate (124) is formed at one end of the third tube body (12) close to the tube body (11); the outer wall of the first tube body (11) protrudes outward to form a ring-shaped portion (101); a ring groove (10b) is formed on the outer end surface of the ring-shaped portion (101); the plate (124) protrudes toward the side of the first tube body (11) to form an outer tube (121); the outer tube (121) extends into the ring groove (10b) and is bonded and sealed to the ring groove (10b).

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