Vibration temperature composite sensor convenient to encapsulate

Abstract

The invention belongs to the field of temperature and vibration detection equipment, and particularly relates to a vibration and temperature composite sensor convenient to encapsulate, which comprises an inner shell assembly, an outer shell assembly and an inner shell assembly, the two circuit boards are installed on the two sides of the installation frame respectively, and a clamping cavity is defined by the two circuit boards and the installation frame. The temperature sensitive element is accommodated in the second shell; the two MEMS vibration sensors are respectively welded on the two circuit boards; one end of the clamping cavity is communicated with the inner cavity of the second shell, and the other end of the clamping cavity is communicated with the inner cavity of the first shell through a through hole; and the inner cavity of the second shell is communicated with the inner cavity of the first shell through a radial channel. According to the invention, the pouring sealant can fully fill the inner cavity of the sensor, and the pore problem caused by a traditional blind hole structure is thoroughly eliminated; meanwhile, non-uniform potting caused by inclination or not-in-place of the circuit board is avoided in a screw fixing mode, so that lines and elements are uniformly wrapped by the potting adhesive, and the reliability of the potting process and the product percent of pass are greatly improved.

Description

Technical Field

[0001] The present invention belongs to the field of temperature and vibration detection devices, and particularly relates to a vibration-temperature composite sensor facilitating potting. Background Art

[0002] Vibration-temperature composite sensors have advantages such as high integration and convenient installation and maintenance, and are widely used in fields such as railway transportation. MEMS (Micro-Electro-Mechanical System) vibration sensors are a vibration detection technology based on micro-electromechanical systems, and their core components are micron-level cantilever beams or mass-spring structures. When the sensor is subjected to external vibration, the inertial force causes the mass block to displace, resulting in changes in the parameters of the piezoresistive, capacitive, or piezoelectric elements connected thereto (such as resistance value, plate spacing, or charge amount). These changes are converted into electrical signals and are processed through amplification and filtering, and finally an electrical signal proportional to the vibration acceleration, frequency, or amplitude is output, realizing the accurate measurement of mechanical vibration into an electrical signal.

[0003] Since the vibration-temperature composite sensor has requirements for the frequency range of vibration acquisition (generally 160 Hz to 8 kHz, ±3 dB), that is, within the specified frequency range, the output of the sensor should not exceed the given deviation. And this performance is proportional to the rigid connection strength between the vibration chip and the vibration source. The greater the rigid connection strength between the vibration chip and the vibration source, the more stable the high-frequency part of the sensor; in the prior art, since the vibration chip and the sensor probe are simply surface-mounted, the rigid connection strength is poor, resulting in the instability of the high-frequency part of the sensor and easy distortion of the acquired signal; specifically, in the prior art, since a groove is provided at the bottom of the inner cavity of the sensor probe, the circuit board with the vibration chip has freedom constraints only on one side, and there are no effective constraints on the other surfaces of the circuit board except the bottom surface. In fact, after the circuit board is placed in the groove, it often tilts, which will increase the transverse sensitivity of the vibration output (the transverse sensitivity is a harmful index of the vibration sensor); and since the inner cavity of the sensor probe is relatively deep, it is not easy to quickly and effectively judge whether the circuit board is fully inserted during actual production; for a biaxial vibration-temperature composite sensor (that is, it is necessary to collect vibration signals in two directions and two circuit boards are required), if the installation is not in place, it will lead to poor consistency of the internal wiring space of the sensor; this results in higher requirements for the potting process operation of the inner cavity of the sensor in the prior art (that is, after the circuit board is stuck in the groove, the inner cavity of the sensor is filled with potting glue such as epoxy resin). It is easy to form a small space between the circuit board and the sensor housing, and the potting glue is not easy to pot the entire space of the inner cavity, resulting in easy breakdown of the insulation withstand voltage of the sensor.

[0004] Secondly, the micro-mechanical structure of a single MEMS chip generally has a flat distribution. When detecting vibrations, aligning the distribution plane of the micro-mechanical structure with the vibration direction of the main vibration source can achieve better detection effects. The installation attitude of the MEMS chip relative to the vibration source is mainly affected by two factors. One is the assembly method between the MEMS chip itself and the sensor housing, and the other is the assembly method between the sensor housing and the vibration source. Even if the existing technology can keep the MEMS chip at a specific angle with the sensor housing, during the installation of the sensor, due to the existence of processing errors, it is still difficult to ensure that the MEMS chip can be at an ideal assembly angle with the vibration source after the thread is rotated in place. Summary of the Invention

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a vibration-temperature composite sensor that is convenient for potting, ensure the reliability of the installation structure of the vibration sensor, and reduce the difficulty of the packaging process.

[0006] To achieve the above and other related purposes, the present invention provides a vibration-temperature composite sensor that is convenient for potting, comprising: An inner shell assembly, the inner shell assembly includes a cylindrical first shell and a second shell, the second shell is connected to the first end wall of the first shell, and the inner cavity of the second shell is communicated with the inner cavity of the first shell; an installation frame protruding axially is provided inside the first end wall; A circuit board, two circuit boards are respectively installed on both sides of the installation frame and enclose a clamping cavity with the installation frame, and the board surface of the circuit board is parallel to the axis of the inner shell assembly; A temperature-sensitive element, housed in the second shell; MEMS vibration sensors, two MEMS vibration sensors are respectively welded to the sides of the two circuit boards facing away from the clamping cavity; One end of the clamping cavity close to the first end wall is communicated with the inner cavity of the second shell, and the end of the clamping cavity far from the first end wall is communicated with the inner cavity of the first shell through a through hole opened on the installation frame; A radial channel is provided inside the first end wall, and the inner cavity of the second shell is communicated with the inner cavity of the first shell through the radial channel; A cable interface is provided on the first shell, and the signal lines of the temperature-sensitive element and the circuit board are led to the cable interface, and the signal line of the temperature-sensitive element passes through the radial channel.

[0007] In an alternative embodiment of the present invention, it further includes a housing assembly. The housing assembly includes a base. A groove for receiving the first housing is provided on the first side of the base. A threaded pipe for connecting the device under test is protrudingly provided on the second side of the base. The inner cavity of the threaded pipe communicates with the groove. The second housing is received in the inner cavity of the threaded pipe. A positioning mechanism is provided on the second side of the base. The positioning mechanism is configured such that when the threaded pipe is connected to the device under test to a preset depth and the base is rotated relative to the device under test to a preset angle, the positioning mechanism can cooperate with a preset positioning groove on the device under test to keep the base at the preset angle. A limiting mechanism is provided between the inner housing assembly and the base. The limiting mechanism is configured to prevent the inner housing assembly from rotating relative to the base.

[0008] In an alternative embodiment of the present invention, it further includes a pre-tightening mechanism. The pre-tightening mechanism is configured such that when the threaded pipe is connected to the device under test to a preset depth and the base is rotated relative to the device under test to a preset angle, the pre-tightening mechanism can generate a pre-tightening force parallel to the axial direction of the threaded pipe between the base and the device under test.

[0009] In an alternative embodiment of the present invention, the pre-tightening mechanism includes a gland and a force transmission medium. The gland is threadedly connected to the base. The force transmission medium penetrates through the base. One end of the force transmission medium abuts against the gland, and the other end of the force transmission medium is used to abut against the surface of the device under test.

[0010] In an alternative embodiment of the present invention, a protrusion is provided on the outer side of the first end wall of the first housing. The protrusion penetrates through the base through a hollow portion provided on the base. The gland abuts against the first housing. The first housing and the protrusion constitute the force transmission medium. The protrusion and the hollow portion constitute the limiting mechanism.

[0011] In an alternative embodiment of the present invention, the positioning mechanism includes a positioning ring. A convex block is provided on the outer peripheral surface of the positioning ring. A ring groove surrounding the threaded pipe is provided on the second side of the base. The positioning ring is sleeved on the root of the threaded pipe. The positioning ring is rotatably provided synchronously with the threaded pipe and is slidably provided along the axial direction of the threaded pipe. An elastic element is provided between the positioning ring and the base. The elastic element is configured such that its elastic force can drive the positioning ring to move away from the base. A holding mechanism is further provided on the second side of the base. The holding mechanism is configured to be able to hold the positioning ring located in the ring groove in the ring groove and release the positioning ring when the holding mechanism is externally squeezed, so that the positioning ring protrudes from the second side of the base under the action of the elastic element.

[0012] In an alternative embodiment of the present invention, the holding mechanism includes a holding frame made of an elastic material. The holding frame is fixed in the annular groove. On one side of the holding frame facing the positioning ring, there are elastic buckles. On the positioning ring, there are card slots that cooperate with the elastic buckles. On the side of the elastic buckle away from the base, there is a convex portion protruding from the second side of the base. The elastic buckle is configured such that when the convex portion is extruded by an external force pointing axially towards the base, the elastic buckle can be separated from the card slot.

[0013] In an alternative embodiment of the present invention, a through hole penetrating the base is provided in the annular groove. A screw is provided in the through hole. At one end of the screw located on the first side of the base, there is a radial flange. The other end of the screw is connected to a threaded hole provided on the positioning ring.

[0014] In an alternative embodiment of the present invention, a buffer pad made of an elastic material is provided between the first end wall of the first housing and the first side of the base.

[0015] In an alternative embodiment of the present invention, the base and the gland have a non-circular outer peripheral surface that can cooperate with a screwing tool.

[0016] The technical effect of the present invention is as follows: By designing the inner housing assembly with an installation frame and optimizing the potting structure, the present invention significantly improves the potting effect. The installation frame regularly fixes the two circuit boards and forms a clamping cavity, which, in cooperation with the top through hole and the radial channel, forms a two-way potting path, ensuring that the potting glue can fully fill the inner cavity of the sensor, especially the communication area between the clamping cavity and the second housing, completely eliminating the porosity problem caused by the traditional blind hole structure. At the same time, the screw fixing method avoids the uneven potting caused by the inclination or improper placement of the circuit board, enabling the potting glue to evenly wrap the circuits and components, greatly improving the reliability of the potting process and the product qualification rate. Description of the Drawings

[0017] Figure 1 is an exploded view of the inner housing assembly provided by the embodiment of the present invention; Figure 2 is an exploded view of the vibration temperature composite sensor provided by the embodiment of the present invention; Figure 3 is a perspective view of the vibration temperature composite sensor provided by the embodiment of the present invention; Figure 4 is Figure 3 a partial enlarged view of I; Figure 5 is an end view of the vibration temperature composite sensor provided by the embodiment of the present invention; Figure 6 is Figure 5 a sectional view taken along line A-A; Figure 7 is Figure 6 a partially enlarged view of part II; Figure 8 is an exploded view of the base and its accessories provided by an embodiment of the present invention; Figure 9 is an exploded view of the positioning ring and the cage provided by an embodiment of the present invention; Explanation of the attached drawings: 10, the first housing; 11, the first end wall; 12, the cylindrical side wall; 13, the second end wall; 14, the radial channel; 15, the cable interface; 16, the protrusion; 17, the mounting frame; 171, the clamping cavity; 18, the through hole; 20, the second housing; 30, the circuit board; 40, the temperature-sensitive element; 50, the base; 51, the threaded tube; 52, the hollowed-out part; 53, the buffer pad; 54, the annular groove; 60, the gland; 70, the positioning ring; 71, the protrusion; 72, the screw; 73, the clamping groove; 80, the cage; 81, the elastic buckle; 82, the protrusion; 90, the elastic element. Detailed implementation manners

[0018] The following illustrates the implementation manners of the present invention through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0019] It should be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner. Therefore, only the components related to the present invention are shown in the diagrams, rather than being drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and ratio of each component in actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0020] Please refer to Figure 1As shown in the figure, the vibration temperature composite sensor provided by the embodiment of the present invention, which is convenient for potting, includes an inner shell assembly, a circuit board 30, a temperature sensitive element 40, and a MEMS vibration sensor; the inner shell assembly includes a cylindrical first shell 10 and a second shell 20, the second shell 20 is connected to the first end wall 11 of the first shell 10, and the inner cavity of the second shell 20 is communicated with the inner cavity of the first shell 10; an installation frame 17 protruding axially is provided inside the first end wall 11; the two circuit boards 30 are respectively installed on both sides of the installation frame 17 and enclose a clamping cavity 171 with the installation frame 17, and the board surface of the circuit board 30 is parallel to the axis of the inner shell assembly; the temperature sensitive element 40 is accommodated in the second shell 20; the two MEMS vibration sensors are respectively welded to the side of the two circuit boards 30 facing away from the clamping cavity 171; one end of the clamping cavity 171 close to the first end wall 11 is communicated with the inner cavity of the second shell 20, and the other end of the clamping cavity 171 away from the first end wall 11 is communicated with the inner cavity of the first shell 10 through a through hole 18 opened on the installation frame 17; a radial channel 14 is provided inside the first end wall 11, and the inner cavity of the second shell 20 is communicated with the inner cavity of the first shell 10 through the radial channel 14; a cable interface 15 is provided on the first shell 10, and the signal lines of the temperature sensitive element 40 and the circuit board 30 are led to the cable interface 15, and the signal line of the temperature sensitive element 40 passes through the radial channel 14.

[0021] By designing the inner shell assembly with the installation frame 17 and optimizing the potting structure, the present invention significantly improves the potting effect. The installation frame 17 regularly fixes the two circuit boards 30 and forms a clamping cavity 171, which cooperates with the top through hole 18 and the radial channel 14 to form a two-way potting path, ensuring that the potting glue can fully fill the inner cavity of the sensor, especially the communication area between the clamping cavity 171 and the second shell 20, and completely eliminating the pore problem caused by the traditional blind hole structure; at the same time, the screw fixing method avoids the uneven potting caused by the inclination or misalignment of the circuit board 30, so that the potting glue evenly wraps the circuits and components, greatly improving the reliability of the potting process and the product qualification rate.

[0022] Please refer to Figure 1 As shown in the figure, in a specific embodiment, for the convenience of processing and potting glue, the first shell 10 can be split into multiple components, such as the first end wall 11, the cylindrical side wall 12, and the second end wall 13. The cable interface 15 can be provided on the second end wall 13. Before potting, the cylindrical side wall 12 can be welded to the first end wall 11 first to form a potting glue space, and then the second end wall 13 is welded to the cylindrical side wall 12 after the potting is completed to form a closed space.

[0023] Please refer to Figures 2 - 9As shown, in an alternative embodiment of the present invention, it further includes a housing assembly. The housing assembly includes a base 50. A groove for receiving the first housing 10 is provided on the first side of the base 50. A threaded tube 51 for connecting the device under test is protrudingly provided on the second side of the base 50. The inner cavity of the threaded tube 51 communicates with the groove, and the second housing 20 is received in the inner cavity of the threaded tube 51. A positioning mechanism is provided on the second side of the base 50. The positioning mechanism is configured such that when the threaded tube 51 is connected to the device under test to a preset depth and the base 50 is rotated relative to the device under test to a preset angle, the positioning mechanism can cooperate with a preset positioning groove on the device under test to keep the base 50 at the preset angle. A limiting mechanism is provided between the inner housing assembly and the base 50. The limiting mechanism is configured to be able to prevent the inner housing assembly from rotating relative to the base 50. Through the cooperation of the depth control of the threaded tube 51 with the positioning mechanism and the positioning groove in this further embodiment, precise angle locking between the sensor housing and the device under test is achieved. Combined with the limiting mechanism between the inner housing assembly and the base 50, it double-guarantees the installation posture of the MEMS vibration chip: when the thread is tightened to the preset depth, the positioning mechanism automatically snaps into the positioning groove of the device under test, forcibly fixing the circumferential angle of the housing assembly. At the same time, the limiting mechanism prevents the inner housing assembly from rotating relatively, ensuring that the sensitive direction of the MEMS chip is always strictly aligned with the main vibration direction of the vibration source, effectively eliminating the installation angle deviation caused by processing errors, and significantly improving the accuracy of vibration signal detection and the frequency response consistency.

[0024] Please refer to Figure 2 , Figure 3 , Figure 5 , Figure 6 As shown, in an alternative embodiment of the present invention, it further includes a pre-tightening mechanism. The pre-tightening mechanism is configured such that when the threaded tube 51 is connected to the device under test to a preset depth and the base 50 is rotated relative to the device under test to a preset angle, the pre-tightening mechanism can generate a pre-tightening force parallel to the axial direction of the threaded tube 51 between the base 50 and the device under test. Through the pre-tightening mechanism applying an axial pre-tightening force when the threaded tube 51 is tightened to the preset depth in this further embodiment, a rigid and close contact is formed between the sensor base 50 and the device under test, effectively eliminating the possible small gaps or looseness existing in traditional threaded connections. This stable mechanical coupling ensures the efficient and lossless transmission of vibration energy from the device under test to the sensor housing. Especially in high-frequency vibration scenarios, it avoids signal attenuation or distortion caused by micro-movement of the contact surface, thereby significantly improving the detection fidelity of the MEMS chip to the original signal of the vibration source and ensuring the measurement accuracy and stability of the sensor in the full frequency band.

[0025] Please refer to Figure 2 , Figure 3 , Figure 5 ,Figure 6 As shown, in an alternative embodiment of the present invention, the pre-tightening mechanism includes a gland 60 and a force transmission medium. The gland 60 is threadedly connected to the base 50. The force transmission medium is disposed through the base 50. One end of the force transmission medium abuts against the gland 60, and the other end of the force transmission medium is used to abut against the surface of the device under test. A protrusion 16 is provided outside the first end wall 11 of the first housing 10. The protrusion 16 passes through the base 50 through a hollow portion 52 provided on the base 50. The gland 60 abuts against the first housing 10. The first housing 10 and the protrusion 16 constitute the force transmission medium, and the protrusion 16 and the hollow portion 52 constitute the limiting mechanism. In this further embodiment, the protrusion 16 of the first housing 10 is used as both the force transmission medium and the limiting mechanism through an integrated design, reducing the number of parts and improving the assembly reliability; the rigid protrusion 16 eliminates signal attenuation that may be caused by an intermediate medium, ensuring that high-frequency vibration is conducted to the MEMS chip without loss; the cooperation between the protrusion 16 and the hollow portion 52 of the base 50 naturally restricts the circumferential rotation of the inner housing assembly while achieving pre-tightening, double-guaranteeing the installation angle accuracy of the MEMS chip; the design of the hollow portion 52 takes into account both the pre-tightening force transmission and the limiting function, avoiding weakening the strength of the base 50 caused by separately machining the limiting structure. This solution significantly optimizes the production feasibility while improving the performance of the sensor.

[0026] Please refer to Figures 3 - 9As shown, in an alternative embodiment of the present invention, the positioning mechanism includes a positioning ring 70. A convex block 71 is provided on the outer peripheral surface of the positioning ring 70. A ring groove 54 is provided on the second side of the base 50 and is arranged to surround the threaded tube 51. The positioning ring 70 is sleeved on the root of the threaded tube 51. The positioning ring 70 is arranged to rotate synchronously with the threaded tube 51 and is arranged to slide axially along the threaded tube 51. An elastic element 90 is provided between the positioning ring 70 and the base 50. The elastic element 90 is configured such that its elastic force can drive the positioning ring 70 to move away from the base 50. A holding mechanism is further provided on the second side of the base 50. The holding mechanism is configured to be able to hold the positioning ring 70 located in the ring groove 54 within the ring groove 54 and to be able to release the positioning ring 70 when the holding mechanism is externally squeezed, so that the positioning ring 70 protrudes from the second side of the base 50 under the action of the elastic element 90. Through the synergistic action of the elastic element 90 and the holding mechanism in this further embodiment, the automatic ejection function of the positioning ring 70 is realized: when the sensor is installed to the preset depth, the surface of the device under test squeezes to trigger the holding mechanism to release the positioning ring 70, and the elastic element 90 immediately pushes the positioning ring 70 to protrude from the surface of the base 50, causing it to automatically snap into the positioning groove of the device under test. This design simplifies the installation operation process, effectively avoids human installation errors, thereby ensuring the strict matching of the sensitive direction of the MEMS vibration chip with the main vibration direction of the vibration source, and significantly improving the accuracy of vibration signal acquisition.

[0027] Please refer to Figures 3 - 9As shown, in an alternative embodiment of the present invention, the holding mechanism includes a holder 80 made of an elastic material. The holder 80 is fixed in the annular groove 54. On one side of the holder 80 facing the positioning ring 70, there is an elastic buckle 81. On the positioning ring 70, there is a clamping groove 73 that cooperates with the elastic buckle 81. On the side of the elastic buckle 81 away from the base 50, there is a convex portion 82 protruding from the second side of the base 50. The elastic buckle 81 is configured to be able to separate the elastic buckle 81 from the clamping groove 73 when the convex portion 82 is externally squeezed by a force pointing axially towards the base 50. The specific principle of the holding mechanism is as follows: When the threaded tube 51 is screwed into the preset depth of the device under test, the surface of the device under test exerts pressure on the convex portion 82. At this time, the elastic buckle 81 collapses, and then the elastic buckle 81 is separated from the clamping groove 73, and the positioning ring 70 pops out. However, at this time, the convex block 71 on the positioning ring 70 may not just align with the notch at the edge of the positioning groove on the device under test. If the two do not align, the positioning ring 70 will not be temporarily popped into the positioning groove. As the threaded tube 51 continues to be screwed, the convex block 71 on the positioning ring 70 will surely reach the position where it aligns with the notch at the edge of the positioning groove. At this time, the positioning ring 70 will pop into the positioning groove, thereby realizing the circumferential fixation between the base 50 and the device under test. This further embodiment realizes the adaptive and precise positioning of the positioning ring 70. When the threaded tube 51 is screwed into the preset depth, the device under test squeezes the convex portion 82 to trigger the separation of the elastic buckle 81 from the clamping groove 73, and the positioning ring 70 enters the state of being ready to be ejected under the action of the elastic element 90; as the threaded tube 51 continues to rotate, the convex block 71 of the positioning ring 70 automatically finds the position until it aligns with the positioning groove notch and then instantly pops in and locks. This pre-triggering plus dynamic calibration mechanism avoids the cumbersome operation of precise alignment required by the traditional positioning method, and can still ensure the precise alignment of the sensitive direction of the MEMS chip and the main vibration direction of the vibration source by 100% in a complex installation environment, greatly improving the installation efficiency and measurement accuracy.

[0028] Please refer to Figure 6 , Figure 7 , Figure 8As shown, in an alternative embodiment of the present invention, a through hole penetrating the base 50 is provided in the annular groove 54. A screw 72 is provided in the through hole. A radial flange is provided at one end of the screw 72 on the first side of the base 50. The other end of the screw 72 is connected to a threaded hole provided on the positioning ring 70. In this further embodiment, by providing the screw 72 with a radial flange in the annular groove 54 to connect the positioning ring 70, the function of quickly and non-destructively disassembling the sensor is achieved; when the sensor needs to be disassembled, only need to tighten the screw 72 from the first side of the base 50, and then the positioning ring 70 can be smoothly withdrawn from the positioning groove of the device under test by the axial tension of the screw 72, while compressing the elastic element 90 to reset the positioning ring 70 into the annular groove 54. This design not only avoids the possible mechanical damage to the positioning ring 70 or the positioning groove during the disassembly of the traditional positioning structure, but also significantly reduces the disassembly operation force through the mechanical advantage ratio of the screw 72, enabling the sensor to quickly disengage from the device under test during maintenance without affecting the repeated use accuracy of the positioning mechanism, greatly improving the maintainability and service life of the product.

[0029] Please refer to Figure 2 , Figure 3 , Figure 6 As shown, in an alternative embodiment of the present invention, a buffer pad 53 made of an elastic material is provided between the first end wall 11 of the first housing 10 and the first side of the base 50. The base 50 and the gland 60 have non-circular outer peripheral surfaces that can cooperate with a screwing tool. The elastic buffer pad 53 can buffer the stress concentration caused by the installation pre-tightening force and prevent rigid extrusion between the first housing 10 and the base 50; the non-circular outer peripheral surfaces designed for the base 50 and the gland 60 are convenient for quick clamping by a standardized tool, and greatly improve the on-site disassembly and assembly efficiency.

[0030] In summary, the present invention significantly improves the potting effect by designing an inner shell assembly with an installation frame 17 and optimizing the potting structure. The installation frame 17 regularly fixes two circuit boards 30 and forms a clamping cavity 171, which, in cooperation with the top through-hole 18 and the radial channel 14, forms a two-way potting path, ensuring that the potting adhesive can fully fill the sensor inner cavity, especially the communication area between the clamping cavity 171 and the second housing 20, completely eliminating the pore problem caused by the traditional blind-hole structure. At the same time, the fixing method with screws 72 avoids uneven potting caused by the inclination or misalignment of the circuit board 30, enabling the potting adhesive to evenly wrap the circuits and components, greatly improving the reliability of the potting process and the product qualification rate. Through the cooperation of the depth control and positioning mechanism of the threaded tube 51 and the positioning groove, the precise angular locking of the sensor housing and the device under test is achieved. Combining with the limiting mechanism between the inner shell assembly and the base 50, it double-guarantees the installation posture of the MEMS vibration chip: when the thread is tightened to the preset depth, the positioning mechanism automatically snaps into the positioning groove of the device under test, forcibly fixing the circumferential angle of the outer shell assembly. At the same time, the limiting mechanism prevents the relative rotation of the inner shell assembly, ensuring that the sensitive direction of the MEMS chip is always strictly aligned with the main vibration direction of the vibration source, effectively eliminating the installation angle deviation caused by processing errors, and significantly improving the accuracy and frequency response consistency of vibration signal detection. When the threaded tube 51 is tightened to the preset depth, the pre-tightening mechanism applies an axial pre-tightening force, forming a rigid and tight contact between the sensor base 50 and the device under test, effectively eliminating the possible small gaps or looseness in traditional threaded connections. This stable mechanical coupling ensures the efficient and lossless transmission of vibration energy from the device under test to the sensor housing. Especially in high-frequency vibration scenarios, it avoids signal attenuation or distortion caused by micro-movement of the contact surface, thereby significantly improving the detection fidelity of the MEMS chip to the original signal of the vibration source and ensuring the measurement accuracy and stability of the sensor in the full frequency band. Through the coordinated action of the elastic element 90 and the retaining mechanism, the automatic ejection function of the positioning ring 70 is realized: when the sensor is installed to the preset depth, the surface of the device under test squeezes to trigger the retaining mechanism to release the positioning ring 70, and the elastic element 90 immediately pushes the positioning ring 70 to protrude from the surface of the base 50, causing it to automatically snap into the positioning groove of the device under test. This design simplifies the installation operation process, effectively avoiding human installation errors, thus ensuring the strict matching of the sensitive direction of the MEMS vibration chip and the main vibration direction of the vibration source, and significantly improving the accuracy of vibration signal acquisition. The adaptive precise positioning of the positioning ring 70 is realized: when the threaded tube 51 is screwed into the preset depth, the protrusion 82 of the device under test is squeezed to trigger the separation of the elastic buckle 81 and the card slot 73, and the positioning ring 70 enters the waiting ejection state under the action of the elastic element 90. As the threaded tube 51 continues to rotate, the protrusion 71 of the positioning ring 70 automatically finds the position until it aligns with the notch of the positioning groove and instantly snaps into the lock.This pre-triggering plus dynamic calibration mechanism avoids the cumbersome operation of precise alignment required by traditional positioning methods, and can still ensure the precise alignment of the sensitive direction of the MEMS chip with the main vibration direction of the vibration source by 100% in a complex installation environment, greatly improving the installation efficiency and measurement accuracy.

[0031] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the claims of the present invention.

[0032] In the description herein, numerous specific details are provided, such as examples of components and / or methods, to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of the specific details or with other devices, systems, components, methods, components, materials, parts, etc. In other instances, well-known structures, materials, or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

Claims

1. A vibration temperature composite sensor convenient for potting, characterized in that, Comprising: An inner shell assembly, the inner shell assembly comprising a cylindrical first housing (10) and a second housing (20), the second housing (20) being connected to a first end wall (11) of the first housing (10), and the inner cavity of the second housing (20) communicating with the inner cavity of the first housing (10); an installation frame (17) protruding axially is provided inside the first end wall (11); A circuit board (30), two of the circuit boards (30) being respectively installed on both sides of the installation frame (17) and enclosing a clamping cavity (171) with the installation frame (17), and the board surface of the circuit board (30) being parallel to the axis of the inner shell assembly; A temperature-sensitive element (40), housed inside the second housing (20); A MEMS vibration sensor, two of the MEMS vibration sensors being respectively welded to one side of the two circuit boards (30) facing away from the clamping cavity (171); One end of the clamping cavity (171) close to the first end wall (11) communicates with the inner cavity of the second housing (20), and the other end of the clamping cavity (171) away from the first end wall (11) communicates with the inner cavity of the first housing (10) through a through hole (18) provided on the installation frame (17); A radial channel (14) is provided inside the first end wall (11), and the inner cavity of the second housing (20) communicates with the inner cavity of the first housing (10) through the radial channel (14); A cable interface (15) is provided on the first housing (10), signal lines of the temperature-sensitive element (40) and the circuit board (30) are led to the cable interface (15), and the signal line of the temperature-sensitive element (40) passes through the radial channel (14).

2. The vibration temperature composite sensor convenient for potting according to claim 1, wherein It further comprises an outer shell assembly, the outer shell assembly comprising a base (50), a groove for housing the first housing (10) is provided on a first side of the base (50), a threaded tube (51) for connecting to a device under test protrudes on a second side of the base (50), the inner cavity of the threaded tube (51) communicates with the groove, and the second housing (20) is housed in the inner cavity of the threaded tube (51); a positioning mechanism is provided on the second side of the base (50), the positioning mechanism is configured such that when the threaded tube (51) is connected to the device under test to a preset depth and the base (50) is rotated relative to the device under test to a preset angle, the positioning mechanism can cooperate with a preset positioning groove on the device under test to keep the base (50) at the preset angle; a limiting mechanism is provided between the inner shell assembly and the base (50), the limiting mechanism is configured to be able to prevent the inner shell assembly from rotating relative to the base (50).

3. The vibration temperature composite sensor convenient for potting according to claim 2, wherein, It further includes a pre-tightening mechanism which is configured to generate a pre-tightening force parallel to the axial direction of the threaded pipe (51) between the base (50) and the device under inspection when the threaded pipe (51) is connected to the device under inspection to a preset depth and the base (50) rotates relative to the device under inspection to a preset angle.

4. The vibration temperature composite sensor facilitating potting according to claim 3, wherein, The pre-tightening mechanism includes a gland (60) and a force transmission medium. The gland (60) is threadedly connected to the base (50). The force transmission medium is arranged through the base (50). One end of the force transmission medium abuts against the gland (60), and the other end of the force transmission medium is used to abut against the surface of the device under inspection.

5. The vibration temperature composite sensor facilitating potting according to claim 4, characterized in that A protrusion (16) is provided outside the first end wall (11) of the first housing (10). The protrusion (16) passes through the base (50) through a hollowed-out portion (52) provided on the base (50). The gland (60) abuts against the first housing (10). The first housing (10) and the protrusion (16) constitute the force transmission medium, and the protrusion (16) and the hollowed-out portion (52) constitute the limiting mechanism.

6. The vibration temperature composite sensor facilitating potting according to claim 2, wherein The positioning mechanism includes a positioning ring (70). A convex block (71) is provided on the outer peripheral surface of the positioning ring (70). A ring groove (54) surrounding the threaded pipe (51) is provided on the second side of the base (50). The positioning ring (70) is sleeved on the root of the threaded pipe (51). The positioning ring (70) is arranged to rotate synchronously with the threaded pipe (51) and slide axially along the threaded pipe (51). An elastic element (90) is provided between the positioning ring (70) and the base (50). The elastic element (90) is configured such that its elastic force can drive the positioning ring (70) to move away from the base (50). A holding mechanism is further provided on the second side of the base (50). The holding mechanism is configured to be able to hold the positioning ring (70) located in the ring groove (54) in the ring groove (54) and release the positioning ring (70) when the holding mechanism is externally squeezed, so that the positioning ring (70) protrudes from the second side of the base (50) under the action of the elastic element (90).

7. The vibration temperature composite sensor facilitating potting according to claim 6, wherein, The holding mechanism includes a holding frame (80) made of an elastic material. The holding frame (80) is fixed in the ring groove (54). An elastic buckle (81) is provided on the side of the holding frame (80) facing the positioning ring (70). A card slot (73) cooperating with the elastic buckle (81) is provided on the positioning ring (70). A convex portion (82) protruding from the second side of the base (50) is provided on the side of the elastic buckle (81) away from the base (50). The elastic buckle (81) is configured to be able to separate the elastic buckle (81) from the card slot (73) when the convex portion (82) is externally squeezed by a force axially pointing to the base (50).

8. The vibration temperature composite sensor convenient for potting according to claim 7, characterized in that, A through hole penetrating through the base (50) is provided in the annular groove (54). A screw (72) is provided in the through hole. A radial flange is provided at one end of the screw (72) on the first side of the base (50). The other end of the screw (72) is connected to a threaded hole provided on the positioning ring (70).

9. The vibration temperature composite sensor convenient for potting according to claim 5, characterized in that, A buffer pad (53) made of an elastic material is provided between the first end wall (11) of the first housing (10) and the first side of the base (50).

10. The vibration temperature composite sensor convenient for potting according to claim 4, characterized in that, The base (50) and the gland (60) have non-circular outer peripheral surfaces that can cooperate with a screwing tool.

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