Sensor with diaphragm fixing assembly and fixing processing method

Abstract

The present invention discloses a sensor having a diaphragm fixing assembly and a fixing processing method. The diaphragm fixing assembly includes a base and a connecting ring arranged on the outer side wall of the diaphragm; an L-shaped recess is provided on the outer side wall of the base, the height of the connecting ring extending toward the L-shaped recess is greater than the depth of the L-shaped recess, the inner side wall of the connecting ring is sleeved on the outer side wall of the L-shaped recess and fixedly connected by welding to achieve fixed installation of the diaphragm and the base; when the connecting ring is assembled on the L-shaped recess, a gap is formed between the diaphragm and the upper end surface of the base; a base through hole is provided at the upper end of the base, and the base through hole is connected to the gap to form a T-shaped oil chamber. The above-mentioned diaphragm fixing assembly is fixed to the base by the connecting ring by providing the connecting ring on the outer side wall of the diaphragm and then welding the diaphragm to the base. The L-shaped protrusion blocks the heat between the welds to avoid affecting the sensing device inside the sensor during welding, thereby improving the reliability of the diaphragm fixing installation.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a sensor with a diaphragm fixing component and a fixing processing method. Background Art

[0002] In order to conduct subtle deformations, the sensor is provided with an oil chamber between the diaphragm and the sensing device. The deformation of the diaphragm is conducted to the sensing device through the oil chamber, so that the sensing device senses the deformation and generates a sensing signal. In traditional technical methods, the diaphragm and the sensing device are usually welded by heat welding. During the welding process of this technology, the heat between the welds will be conducted to the sensing device inside the sensor, causing the internal material to melt and shrink upon cooling. This process will generate stress that squeezes the oil chamber, causing the oil chamber to deform, and even cause holes to form on the side wall of the oil chamber, making the produced sensing device unable to sensitively sense vibration deformation and unqualified, affecting the yield rate of the produced product. Therefore, the sensor structure in the prior art has the problem of low reliability of the diaphragm fixed installation. Summary of the Invention

[0003] The present invention provides a sensor with a diaphragm fixing assembly and a fixing processing method thereof, aiming to solve the problem of low reliability of diaphragm fixing installation in sensor structures in the prior art.

[0004] In a first aspect, the present invention discloses a diaphragm fixing assembly, the diaphragm fixing assembly comprising a base and a connecting ring provided on an outer side wall of the diaphragm;

[0005] An L-shaped recess is provided on the outer wall of the base, the height of the connecting ring extending toward the L-shaped recess is greater than the depth of the L-shaped recess, the inner side wall of the connecting ring is sleeved on the outer wall of the L-shaped recess and fixedly connected by welding, so as to achieve fixed installation of the diaphragm and the base; when the connecting ring is assembled on the L-shaped recess, a gap is formed between the diaphragm and the upper end surface of the base; a base through hole is provided at the upper end of the base, and the base through hole is connected to the gap to form a T-shaped oil chamber;

[0006] The base is made of aluminum or aluminum alloy, and the diaphragm and the connecting ring are integrally formed with aluminum or aluminum alloy.

[0007] In a second aspect, the present invention discloses a sensor, wherein the sensor comprises the diaphragm fixing assembly as described in the first aspect, and the sensor further comprises a circuit board;

[0008] A base cavity is provided on a side of the base facing away from the diaphragm, and the base cavity is connected to the base through hole;

[0009] The circuit board is fixedly assembled in the base cavity and seals the upper portion of the base through hole to form a T-shaped oil cavity, and oil is injected into the T-shaped oil cavity;

[0010] The circuit board is provided with a circuit board through hole connected to the base through hole; a sealing solder ball is provided at the opening of the circuit board through hole; and a sensor chip and connecting leads are also provided on the circuit board.

[0011] In a third aspect, the present invention further discloses a fixing processing method, wherein the fixing processing method is used to process and manufacture the sensor as described in the second aspect above, wherein the fixing processing method comprises:

[0012] Fixing the circuit board in the base cavity;

[0013] Press-fitting the diaphragm onto the L-shaped recessed platform of the base, and welding the connecting ring to the L-shaped recessed platform;

[0014] After oil is injected into the T-shaped oil cavity through the circuit board through hole, molten solder balls are used to fill the openings of the circuit board through holes to form sealed solder balls.

[0015] The present invention discloses a sensor having a diaphragm fixing assembly and a fixing processing method. The diaphragm fixing assembly includes a base and a connecting ring arranged on the outer side wall of the diaphragm; an L-shaped recess is provided on the outer side wall of the base, the height of the connecting ring extending toward the L-shaped recess is greater than the depth of the L-shaped recess, the inner side wall of the connecting ring is sleeved on the outer side wall of the L-shaped recess and fixedly connected by welding to achieve fixed installation of the diaphragm and the base; when the connecting ring is assembled on the L-shaped recess, a gap is formed between the diaphragm and the upper end surface of the base; a base through hole is provided at the upper end of the base, and the base through hole is connected to the gap to form a T-shaped oil chamber. The above-mentioned diaphragm fixing assembly is fixed to the base by the connecting ring by providing a connecting ring on the outer side wall of the diaphragm and then welding the diaphragm to the base. The L-shaped boss blocks the heat between the welds to prevent the welding from affecting the sensing device inside the sensor, thereby improving the reliability of the diaphragm fixing installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 An overall structural diagram of a sensor provided by an embodiment of the present invention;

[0018] Figure 2Another overall structural diagram of the sensor provided by an embodiment of the present invention;

[0019] Figure 3 A cross-sectional structural diagram of a sensor provided by an embodiment of the present invention;

[0020] Figure 4 Another cross-sectional structural diagram of a sensor provided by an embodiment of the present invention;

[0021] Figure 5 A partial structural diagram of a sensor provided in an embodiment of the present invention;

[0022] Figure 6 A flow chart of a fixing processing method provided in an embodiment of the present invention.

[0023] Figure numbers: 1. Base; 2. Circuit board; 3. Diaphragm; 11. Base through hole; 31. Connecting ring; 33. Diaphragm convex ring; 32. T-shaped oil chamber; 311. Inner cut corner; 312. Outer cut corner; 12. Base concave cavity; 21. Circuit board through hole; 22. Sensor chip; 23. Connecting lead; 211. Sealing solder ball; 101. Annular protrusion; 201. Annular groove; 4. Pressing ring; 41. Injection molded part; 42. Spacer. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] It will be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0026] It should also be understood that the terms used in the present specification are only for the purpose of describing particular embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0027] It should be further understood that the terms "and, or" used in the present description and the appended claims refer to and include any and all possible combinations of one or more of the associated listed items.

[0028] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

[0029] The present invention discloses a diaphragm fixing assembly, such as Figure 3 As shown, the diaphragm 3 fixing assembly includes a base 1 and a connecting ring 31 arranged on the outer side wall of the diaphragm 3; an L-shaped recess is provided on the outer side wall of the base 1, and the height of the connecting ring 31 extending toward the L-shaped recess is greater than the depth of the L-shaped recess, and the inner side wall of the connecting ring 31 is sleeved on the outer side wall of the L-shaped recess and fixedly connected by welding to achieve fixed installation of the diaphragm 3 and the base 1; when the connecting ring 31 is assembled on the L-shaped recess, a gap is provided between the diaphragm 3 and the upper end surface of the base 1; a base through hole 11 is provided at the upper end of the base 1, and the base through hole 11 is connected to the gap to form a T-shaped oil chamber; the base 1 is made of aluminum or aluminum alloy, and the diaphragm 3 and the connecting ring 31 are integrally formed with aluminum or aluminum alloy.

[0030] The diaphragm 3 is fixedly mounted on the base 1 by pressing the connecting ring 31 onto the base 1. The inner side wall of the connecting ring 31 abuts against the L-shaped recess, and the connecting ring 31 and the base 1 can be fixedly welded by welding. Specifically, since the base 1 is made of aluminum or aluminum alloy, and the connecting ring 31 is also made of aluminum or aluminum alloy, the connecting ring 31 and the base 1 can be welded by laser melting welding, and the welding temperature is 450-700°C. Compared with the technical method of using stainless steel as the material of the diaphragm 3 (the welding temperature of stainless steel is above 1400°C) and welding, the use of aluminum or aluminum alloy to manufacture the connecting ring 31 and the base 1 can greatly reduce the temperature of welding the connecting ring 31 and the base 1, thereby avoiding excessively high temperature to generate strong stress and squeeze the oil chamber. By setting up an L-shaped recess, the heat between the welds can be isolated by the vertical side of the L-shaped recess, and the vertical side of the L-shaped recess is tightly connected to the inner side wall of the connecting ring 31. During the welding process, only the horizontal side of the L-shaped recess and the bottom surface of the connecting ring 31 will be melt-welded, which can prevent heat from being conducted to the gap between the diaphragm 3 and the upper end surface of the base 1, thereby preventing the welding operation from affecting the vertical side of the L-shaped recess, the T-shaped oil chamber 32 (the oil chamber is not in contact with the vertical side of the L-shaped recess) and the sensing device at the base through hole 11, thereby improving the reliability of fixing the diaphragm 3 on the base 1 by welding, and thus improving the yield rate of sensor production.

[0031] In a more specific embodiment, the connecting ring 31 and the L-shaped recess are connected by an interference fit. The inner sidewall of the connecting ring 31 can be configured to be connected by an interference fit with the vertical side of the L-shaped recess. Specifically, the inner diameter of the connecting ring 31 is smaller than the outer diameter of the outer peripheral side of the L-shaped recess (at the same ambient temperature). This configuration allows the vertical side of the L-shaped recess to be tightly connected and sealed with the inner sidewall of the connecting ring 31, further improving the sealing reliability of the T-shaped oil chamber 32 and preventing stress generated during welding that could squeeze the oil chamber and cause deformation of the oil chamber.

[0032] During the specific connection process, the connecting ring 31 can be heated and the base 1 can be cooled. While maintaining a large temperature difference between the two devices, the inner wall of the connecting ring 31 is sleeved on the outer wall of the L-shaped recess and fixedly connected by welding. After welding is completed, a tight seal can be achieved between the connecting ring 31 and the base 1 based on interference fit.

[0033] During the connection process, the inner diameter of the connecting ring 31 can be set to be no larger than the outer diameter of the outer peripheral side of the L-shaped recess. Based on this structural setting, the diaphragm 3 can be assembled by press-fitting. Specifically, a press-fitting force can be applied to the side of the connecting ring 31 facing away from the base 1. This press-fitting force presses the inner sidewall of the connecting ring 31 onto the outer sidewall of the L-shaped recess, and then securely connected by welding.

[0034] In a more specific embodiment, an inner sidewall of the connecting ring 31 facing one end of the base 1 is provided with an inner chamfer 311. Specifically, an outer sidewall of the connecting ring 31 facing one end of the base 1 is provided with an outer chamfer 312.

[0035] Furthermore, in order to improve the convenience of assembling the connecting ring 31 on the base 1, an inner cut corner 311 can be provided on the inner side wall of the connecting ring 31 facing one end of the base 1. The specific structure is as follows: Figure 5 When the connecting ring 31 is pressed and assembled onto the base 1 by external force, the L-shaped recess can slide smoothly into the concave cavity of the connecting ring 31 along the inner cut corner 311. In other words, there is no need for precise alignment between the connecting ring 31 and the L-shaped recess. Even with slight positional deviations, the connecting ring 31 can still be assembled smoothly. This arrangement can improve the assembly efficiency of the connecting ring 31 and the diaphragm 3.

[0036] In order to improve the reliability of welding the connecting ring 31 and the base 1, an outer cut corner 312 can be set on the outer side wall of the connecting ring 31 toward one end of the base 1. The specific structure is as follows: Figure 5 The welding area of ​​the welding operation can be expanded by the gap between the outer chamfer 312 and the horizontal plane of the L-shaped concave table, thereby improving the stability of the connecting ring 31 and the base 1 for welding and fixing.

[0037] In a more specific embodiment, the horizontal side length of the L-shaped concave platform is 0.6-4 mm, wherein the vertical side length of the L-shaped concave platform is 1.5-3.2 times the horizontal side length of the L-shaped concave platform.

[0038] Furthermore, to enhance the stability of the weld between the horizontal side of the L-shaped recess and the connecting ring 31, the length of the horizontal side of the L-shaped recess can be set to 0.6-4 mm. This ensures that the contact area between the horizontal side of the L-shaped recess and the connecting ring 31 is sufficient for a secure weld, thereby enhancing the stability of the weld between the L-shaped recess and the connecting ring 31. Furthermore, to ensure that the vertical side of the L-shaped recess effectively isolates the heat between the weld seams, the length of the vertical side of the L-shaped recess can be set to 1.5-3.2 times the length of the horizontal side to ensure effective isolation of welding heat.

[0039] In a more specific embodiment, the outer wall of the diaphragm 3 is further provided with a diaphragm protrusion 33. The extension direction of the diaphragm protrusion 33 is opposite to the extension direction of the connecting ring 31, and the height of the diaphragm protrusion 33 is less than the height of the connecting ring 31. Specifically, the height of the diaphragm protrusion 33 is 0.12-0.4 times the height of the connecting ring 31.

[0040] In order to improve the tensile strength of the diaphragm 3, a diaphragm convex ring 33 may be provided on the outer end face of the diaphragm 3. The extending direction of the diaphragm convex ring 33 is opposite to the extending direction of the connecting ring 31. The specific structure is as follows: Figures 1 to 3 As shown. The inner diameter of the diaphragm protrusion 33 can be set equal to the inner diameter of the connecting ring 31, and the outer diameter of the diaphragm protrusion 33 can be set equal to the outer diameter of the connecting ring 31. Since the diaphragm protrusion 33 does not need to be set according to the depth of the L-shaped recess, the height of the diaphragm protrusion 33 can be set smaller than the height of the connecting ring 31. The connecting ring 31, diaphragm 3, and diaphragm protrusion 33 can be manufactured by integral molding. In a specific embodiment, the height of the diaphragm protrusion 33 can be set to 0.12-0.4 times the height of the connecting ring 31.

[0041] The embodiment of the present invention also discloses a sensor, such as Figures 1 to 5 As shown, the sensor includes a diaphragm 3 fixing assembly as described in the above embodiment, and a circuit board 2. A base cavity 12 is provided on the side of the base 1 facing away from the diaphragm 3, and the base cavity 12 is connected to the base through hole 11. The circuit board 2 is fixedly assembled in the base cavity 12 and seals the upper portion of the base through hole 11 to form a T-shaped oil chamber 32, into which oil is injected. The circuit board 2 is provided with a circuit board through hole 21 that communicates with the base through hole 11. A sealing solder ball 211 is provided at the opening of the circuit board through hole 21. The circuit board also has a sensor chip 22 and connecting leads 23. The circuit board 2 can be a ceramic plate or a gold-plated carbon steel plate.

[0042] Among them, the sealing solder ball 211 is used to seal the circuit board through hole 21 to provide a sealed environment for the T-shaped oil cavity 32, and oil is injected into the T-shaped oil cavity 32. The sensor chip 22 and the connecting lead 23 are used to sense the vibration deformation and obtain the corresponding sensing signal. The inner diameter of the base through hole 11 can be smaller than the inner diameter of the base cavity 12. The structure is set as follows Figure 4 As shown; the inner diameter of the base through hole 11 can also be set to be greater than or equal to the inner diameter of the base cavity 12, and the structure can be set as Figure 2 and 3 shown.

[0043] The embodiment of the present invention further discloses a fixing processing method, which is used to process and manufacture the sensor as described in the above embodiment. Figure 6 As shown, the fixing processing method specifically includes steps S110 to S130.

[0044] S110, fixing the circuit board in the base cavity.

[0045] Specifically, the circuit board 2 can be fixedly assembled in the base cavity 12. Specifically, the circuit board 2 can be bonded and fixed to the bottom surface of the base cavity 12 by adhesive. The specific structure is as follows: Figure 4 As shown, an annular groove 201 is provided on the circuit board 2, and an annular protrusion 101 is provided on the bottom surface of the base cavity 12. The annular protrusion 101 is assembled in the annular groove 201. At this time, the upper end surface of the circuit board 2 is in contact with the bottom surface of the base cavity 12. Since a connection gap is formed between the annular protrusion 101 and the annular groove 201, adhesive can be injected into the connection gap to fix the annular protrusion 101 and the annular groove 201. Then, the pressure ring 4 is pressed onto the side of the circuit board 2 away from the diaphragm 3 and the pressure ring 4 is welded to the inner side of the base cavity 12, so that the circuit board 2 and the bottom surface of the base cavity 12 are firmly connected. Alternatively, an injection molded part 41 is formed by injection molding and sintering to fix the circuit board 2 and the base cavity 12. The specific structure is as follows. Figure 3 As shown, in this structure, two injection holes are provided on the circuit board 2, a spacer plate 42 is provided in the base through hole 11, and two spacer plate through holes corresponding to the injection holes are provided on the spacer plate 42. One injection hole in the circuit board 2 is used to pass a circulated liquid injection plasticizer, and the other injection hole is used to reflux the excess liquid injection plasticizer when the base through hole 11 is filled with liquid injection plasticizer; after the injection molding is completed, sintering is performed to obtain the injection molded part 41 to fix the circuit board 2 in the base cavity 12.

[0046] S120, press-fitting the diaphragm onto the L-shaped recessed platform of the base, and welding and fixing the connecting ring to the L-shaped recessed platform.

[0047] The diaphragm is pressed and assembled on the L-shaped recess, and the inner side wall of the connecting ring abuts against the side of the L-shaped recess. The connecting ring and the L-shaped recess can then be welded and fixed by heat welding. The welding operation is laser melting welding, and the welding temperature is 450-700°C; the pressure for pressing and assembling the diaphragm is 100-500kg.

[0048] S130 , after injecting oil into the T-shaped oil cavity through the circuit board through hole, use molten solder balls to fill the openings of the circuit board through holes to form sealed solder balls.

[0049] After the diaphragm is fixed and assembled, oil can be injected into the T-shaped oil cavity through the circuit board through-hole. Then, molten solder balls are used to fill the opening of the circuit board through-hole. The molten solder balls are cold-cut to form sealing solder balls, which can achieve a tight seal on the opening of the circuit board through-hole.

[0050] The present invention discloses a sensor having a diaphragm fixing assembly and a fixing processing method. The diaphragm fixing assembly includes a base and a connecting ring arranged on the outer side wall of the diaphragm; an L-shaped recess is provided on the outer side wall of the base, the height of the connecting ring extending toward the L-shaped recess is greater than the depth of the L-shaped recess, the inner side wall of the connecting ring is sleeved on the outer side wall of the L-shaped recess and fixedly connected by welding to achieve fixed installation of the diaphragm and the base; when the connecting ring is assembled on the L-shaped recess, a gap is formed between the diaphragm and the upper end surface of the base; a base through hole is provided at the upper end of the base, and the base through hole is connected to the gap to form a T-shaped oil chamber. The above-mentioned diaphragm fixing assembly is fixed to the base by the connecting ring by providing a connecting ring on the outer side wall of the diaphragm and then welding the diaphragm to the base. The L-shaped boss blocks the heat between the welds to prevent the welding from affecting the sensing device inside the sensor, thereby improving the reliability of the diaphragm fixing installation.

[0051] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present application, and such modifications or substitutions should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A diaphragm fixing assembly, characterized in that: The diaphragm fixing assembly includes a base and a connecting ring arranged on the outer side wall of the diaphragm; An L-shaped recess is provided on the outer wall of the base, the height of the connecting ring extending toward the L-shaped recess is greater than the depth of the L-shaped recess, the inner side wall of the connecting ring is sleeved on the outer wall of the L-shaped recess and fixedly connected by welding, so as to achieve fixed installation of the diaphragm and the base; when the connecting ring is assembled on the L-shaped recess, a gap is formed between the diaphragm and the upper end surface of the base; a base through hole is provided at the upper end of the base, and the base through hole is connected to the gap to form a T-shaped oil chamber; The base is made of aluminum or aluminum alloy, and the diaphragm and the connecting ring are integrally formed with aluminum or aluminum alloy; the vertical side length of the L-shaped recess is 1.5-3.2 times the horizontal side length of the L-shaped recess; the diaphragm is press-fitted onto the L-shaped recess, and the connecting ring and the L-shaped recess are welded and fixed by heat welding, and the welding temperature is 450-700°C.

2. The diaphragm fixing assembly according to claim 1, characterized in that: The connecting ring and the L-shaped recess are connected by interference fit.

3. The diaphragm fixing assembly according to claim 2, characterized in that: An inner side bevel is provided on an inner side wall of the connecting ring facing one end of the base.

4. The diaphragm fixing assembly according to any one of claims 1 to 3, characterized in that: An outer sidewall of the connecting ring is provided with an outer cut corner toward one end of the base.

5. The diaphragm fixing assembly according to claim 4, characterized in that: The horizontal side length of the L-shaped concave platform is 0.6-4 mm.

6. The diaphragm fixing assembly according to claim 4, characterized in that: The outer side wall of the diaphragm is further provided with a diaphragm convex ring, the extension direction of the diaphragm convex ring is opposite to the extension direction of the connecting ring, and the height of the diaphragm convex ring is smaller than the height of the connecting ring.

7. The diaphragm fixing assembly according to claim 6, characterized in that: The height of the diaphragm protrusion ring is 0.12-0.4 times the height of the connecting ring.

8. A sensor, characterized in that: The sensor comprises the diaphragm fixing assembly according to any one of claims 1 to 7, and the sensor further comprises a circuit board; A base cavity is provided on a side of the base facing away from the diaphragm, and the base cavity is connected to the base through hole; The circuit board is fixedly assembled in the base cavity and seals the upper portion of the base through hole to form a T-shaped oil cavity, and oil is injected into the T-shaped oil cavity; The circuit board is provided with a circuit board through hole connected to the base through hole; a sealing solder ball is provided at the opening of the circuit board through hole; and a sensor chip and connecting leads are also provided on the circuit board.

9. A fixing processing method, said fixing processing method being used for processing and manufacturing the sensor according to claim 8, characterized in that: The fixing processing method comprises: Fixing the circuit board in the base cavity; Press-fitting the diaphragm onto the L-shaped recessed platform of the base, and welding the connecting ring to the L-shaped recessed platform; After oil is injected into the T-shaped oil cavity through the circuit board through hole, molten solder balls are used to fill the openings of the circuit board through holes to form sealed solder balls.

Images