A composite sensor based on a compression-expansion structure, its assembly method, and its sensing method.

Abstract

This invention belongs to the field of sensor technology, specifically relating to a composite sensor based on a compression-expansion structure, its assembly method, and sensing method. The sensor consists of an upper housing and a lower housing connected by threads. An acceleration core assembly is mounted on the upper housing, sensing impact acceleration through a mass block-piezoelectric ceramic structure. A force core assembly is placed on a threaded post, converting static compressive force laterally into a piezoelectric ceramic charge signal via a conical support block. A pressure core assembly is installed within the pressure-sensitive assembly hole of the lower housing, generating a signal through lateral expansion driven by external pressure via a conical diaphragm. The signal is output through a wire hole inside the housing and a four-pin connector. The acceleration, force, and pressure composite sensing are integrated into one unit, with a detachable threaded connection for easy core maintenance and replacement. Insulating rings and blocks provide electrical isolation between the cores, offering strong anti-interference capabilities. Internal wiring ensures reliable protection.

Description

Technical Field

[0001] This invention belongs to the field of sensor technology, specifically relating to a composite sensor based on a compression-expansion structure, its assembly method, and its sensing method. Background Technology

[0002] In piezoelectric sensor technology, acceleration, force, and pressure sensors based on piezoelectric ceramics have been widely used.

[0003] During measurement, three independent sensors are used. Using multiple independent sensors separately and installing them side-by-side introduces axial misalignment and phase delay, resulting in low stability of the measured acceleration, static force, and pressure signals, and poor measurement reliability. Furthermore, the individual use of multiple sensors requires separate connection to signal interfaces and cables, increasing the risk of external electromagnetic interference and further reducing measurement reliability. Summary of the Invention

[0004] This invention provides a composite sensor based on a compression-expansion structure. This invention integrates acceleration, force, and pressure sensing into a single unit, with a threaded, detachable connection for easy core maintenance and replacement. Insulating rings and blocks provide electrical isolation between the individual cores, resulting in strong anti-interference capabilities.

[0005] The composite sensor includes: a core assembly, an upper housing, and a lower housing; One end of the upper housing has a core assembly hole, and an acceleration core assembly for sensing impact acceleration is installed inside the core assembly hole. The upper housing is provided with an inner groove, and a threaded post is provided in the middle of the inner groove; the first end of the lower housing is provided with a threaded countersunk hole that matches the threaded post; the lower housing and the upper housing are detachably connected by threads. The force core assembly is mounted on the threaded post of the upper housing and abuts against the threaded counterbore wall of the lower housing. The force core assembly is used to convert the externally applied static compressive force into lateral extrusion force through compression and expansion, so that the piezoelectric ceramic generates an electric charge signal to realize force signal monitoring. The lower housing has a pressure-sensitive assembly hole at the second end. Inside the pressure-sensitive assembly hole is a pressure core assembly that uses a conical diaphragm to withstand external pressure, drives a conical support block to expand laterally, and causes the piezoelectric ceramic to generate an electric charge signal, thereby realizing pressure signal monitoring.

[0006] Based on the above-mentioned composite sensor, the present invention provides an assembly method, the assembly method comprising: Signal core wires were welded to the center of the electrode sheet, the outer metal layer of the force core cylindrical ceramic, and the outer metal layer of the pressure core cylindrical ceramic, respectively, to obtain three signal core wires for acceleration, force, and pressure. The accelerometer core insulating ring is attached to the inner wall of the core assembly hole at the first end of the upper housing. The accelerometer core insulating block, electrode sheet, accelerometer core sheet ceramic, accelerometer core mass block and accelerometer core cover block are stacked in sequence at the bottom of the hole. The accelerometer signal core wire is passed out from the wire hole of the threaded column of the upper housing. After applying the pre-tightening force, the sealing cover block is welded. The first force core insulating ring is placed against the bottom of the groove inside the upper housing. The force core conical insulating block is fitted onto the outer wall of the threaded column. The force core conical support block is fitted onto the outer wall of the conical insulating block. The force core cylindrical ceramic is fitted onto the outer wall of the support block. The second force core insulating ring is fitted onto the end of the ceramic and abuts against the outer wall of the threaded countersunk hole of the lower housing. The force signal core wire is passed out from the connector hole of the upper housing. The lower housing and the upper housing are screwed together to the set torque and then welded and fixed. Place the pressure core insulating seat at the bottom of the pressure-sensitive assembly hole at the second end of the lower housing, place the pressure core conical support block on the insulating seat, fit the pressure core cylindrical ceramic, fit the pressure core insulating ring on the connection between the cone head and the flat section of the pressure core conical diaphragm, insert the cone head inward into the pressure-sensitive assembly hole so that the cone head contacts the inner conical surface of the support block and the flat section abuts against the end step of the hole, apply pre-tightening force, weld the sealing flat section to the lower housing, and pass the pressure signal core wire out from the lower lead wire hole of the lower housing; The three signal core wires are led through the internal channel of the housing to the connector hole and soldered to the four pins of the four-core connector respectively; The four-pin connector is inserted into the connector hole on the upper housing and sealed and fixed by laser welding.

[0007] The present invention also provides a sensing method, the sensing method comprising: When the annular boss of the upper shell is subjected to static compressive force, the compressive force is transmitted through the upper shell to the conical insulating block, which wedges downward into the conical support block of the force core. The conical support block of the force core expands radially and squeezes the cylindrical ceramic of the force core to generate force signal charge, which is output to the four-core connector through the force signal core wire. When the conical diaphragm of the pressure core at the bottom of the housing is subjected to external pressure, the flat section moves upward, causing the cone head to push the conical support block of the pressure core. The conical support block of the pressure core expands radially, squeezing the cylindrical ceramic of the pressure core to generate a pressure signal charge, which is output to the four-core connector through the pressure signal core wire. When the sensor as a whole is subjected to axial vibration or impact acceleration, the mass block of the acceleration core generates inertial force that compresses the ceramic sheet of the acceleration core to generate acceleration signal charge, which is output to the four-pin connector through the electrode sheet of the acceleration core. The four-pin connector transmits at least one received charge signal to the signal acquisition device via an external cable.

[0008] As can be seen from the above technical solutions, the present invention has the following advantages: The pressure core assembly of this invention is installed at the bottom of the lower housing, directly sensing the external medium pressure and driving another set of conical expansion mechanisms. The acceleration core assembly is encapsulated in the upper housing, sensing vibration through a core mass block. The three sensing units share the same axis, with the force and acceleration transmission paths mechanically isolated but structurally integrated. This design integrates multiple signal acquisitions, eliminating the axis deviation and phase delay problems associated with juxtaposing multiple sensors, resulting in spatial consistency and temporal synchronization of the measured acceleration, static force, and pressure signals, thus improving measurement reliability.

[0009] The core insulating block of this invention serves both insulation and positioning functions. All components are pressed into a rigid cavity formed by the core assembly holes in the upper shell, and a complete seal is achieved through welding of the cover block. This provides the acceleration core assembly with rigid support and axial positioning, enabling it to capture high-frequency vibration signals. The embedded encapsulation structure isolates the acceleration core assembly from the transmission path of external force loads, and prevents deformation of the outer shell and the acceleration core assembly, reducing cross-interference.

[0010] The pressure core assembly is mounted in a countersunk hole at the bottom of the lower housing, structurally connected in series with the force and acceleration sensors above, but mechanically isolated. The pressure signal is sensed through a diaphragm and does not couple with the upper housing boss that measures static force, thus avoiding crosstalk between the two signals. The conical diaphragm design ensures the flexibility required for pressure sensitivity, while the conical head structure provides the rigidity to drive the conical support block, ensuring the sensitivity and stability of the pressure signal conversion. This allows the sensor to accurately measure both static load and dynamic pressure simultaneously.

[0011] During assembly, all signal wires of sensitive components pass through pre-designed insulated channels inside the housing and are soldered together to a four-pin connector. This ensures that the charge signal is shielded and protected by the metal housing throughout the transmission path, reducing electromagnetic interference. Attached Figure Description

[0012] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 A cross-sectional view of a composite sensor based on a compression-expansion structure; Figure 2 This is a schematic diagram of a composite sensor based on a compression-expansion structure. Figure 3 Exploded view of a composite sensor based on a compression-expansion structure; Figure 4 This is a schematic diagram of the upper shell; Figure 5 This is a schematic diagram of the lower shell; Figure 6 A schematic diagram of the pressure-sensitive assembly holes for the lower housing; Figure 7 This is a schematic diagram of a conical support block; Figure 8 Schematic diagram of the conical diaphragm of the pressure core; Figure 9 Schematic diagram of the pressure core insulation seat; Figure 10 This is a schematic diagram of a cone-shaped insulating block; Figure 11 Schematic diagram of the cone-shaped support block for the force core; Figure 12 This is a schematic diagram of a four-pin connector.

[0014] Explanation of reference numerals in the attached figures: 1-Upper shell, 2-First force core insulating ring, 3-Cylindrical ceramic, 4-Conical insulating block, 5-Force core conical support block, 6-Lower shell, 7-Pressure core insulating seat, 8-Pressure core cylindrical ceramic, 9-Conical support block, 10-Pressure core conical diaphragm, 11-Pressure core insulating ring, 12-Core cover block, 13-Core insulating ring, 14-Core sheet ceramic, 15-Electrode sheet, 16-Core insulating block, 17-Core mass block, 18-Four-core connector, 20-Second force core insulating ring, 21-Wire hole, 22-Lower wire hole. Detailed Implementation

[0015] The following describes in detail the composite sensor based on a compression-expansion structure according to this application. Specific details, such as particular system structures and techniques, are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application can also be implemented in other embodiments without these specific details.

[0016] like Figures 1 to 12 As shown, the sensor includes: a force core assembly, an upper housing 1, and a lower housing 6.

[0017] The upper housing 1 provides overall support and installation space. An annular boss at one end of the upper housing 1 is used for force transmission. An acceleration core assembly for sensing impact acceleration is built into the core assembly hole. The upper housing 1 is provided with an inner groove, and a threaded post is provided in the middle of the inner groove. The lower housing 6 has a threaded countersunk hole at its first end that matches the threaded post. The lower housing 6 and the upper housing 1 are detachably connected by threads.

[0018] The force core assembly is installed on the threaded post of the upper housing 1 and abuts against the threaded countersunk hole wall of the lower housing 6. The force core assembly is used to convert the externally applied static compressive force into lateral extrusion force through compression and expansion, so that the piezoelectric ceramic generates an electric charge signal to realize force signal monitoring. The second end of the lower housing 6 is provided with a pressure-sensitive assembly hole, and a pressure core assembly is installed inside the pressure-sensitive assembly hole. This assembly is used to withstand external pressure through a conical diaphragm, drive the conical support block to expand laterally, so that the piezoelectric ceramic generates an electric charge signal to realize pressure signal monitoring.

[0019] It should be noted that the annular boss on the upper shell 1 serves as the force input interface, bearing the external static compressive force. This force is transmitted through the upper shell to the internally installed force core assembly. This force core assembly does not directly sense the axial force; instead, it converts the axial pressure into a radial, uniform expansion force through an internal conical wedge structure. This conversion process causes the cylindrical ceramic 3, fitted on the outside, to experience uniform lateral compression, generating a high-charge signal based on the piezoelectric effect.

[0020] The pressure core assembly of this invention is installed at the bottom of the lower housing 6, directly sensing the external medium pressure and driving another set of conical expansion mechanisms. The acceleration core assembly is encapsulated in the upper housing and senses vibration through the core mass block 17. The three sensing units share the same axis, and the transmission paths of force and acceleration are mechanically isolated but structurally integrated.

[0021] As can be seen, this design integrates multiple signal acquisitions, eliminating the axial misalignment and phase delay issues that occur when multiple sensors are installed side-by-side. This ensures that the measured acceleration, static force, and pressure signals have spatial consistency and temporal synchronization. The sensor structure is integrated into a single unit through threaded pre-tightening and welded sealing. The internal pre-tightening force remains stable under vibration, improving measurement reliability.

[0022] Specifically, the acceleration core assembly of the present invention includes: a core cover block 12, a core insulating ring 13, a core sheet ceramic 14, an electrode sheet 15, a core insulating block 16, and a core mass block 17.

[0023] The core insulating ring 13 is fitted onto the core assembly hole wall to achieve circumferential insulation of the core assembly hole wall; the core insulating block 16 is set at the bottom of the core assembly hole, and the upper end of the core insulating block 16 is sequentially provided with an electrode sheet 15, a core sheet ceramic 14, a core mass block 17, and a core cover block 12.

[0024] It should be noted that the core sheet ceramic 14 and the electrode sheet 15 are sandwiched in the middle by the core mass block 17 and the core cover block, forming a series pressure-bearing structure of mass block-piezoelectric sheet-base.

[0025] When the sensor is subjected to axial vibration, the inertial force generated by the core mass block 17 acts on the core sheet ceramic, generating an electric charge proportional to the acceleration.

[0026] The core insulating ring 13 fits against the core mounting hole wall, providing insulation and eliminating any friction or collision interference between the piezoelectric ceramic side and the metal housing, ensuring that the charge signal originates only from inertial force.

[0027] The bottom core insulating block 16 serves for insulation and positioning. All components are pressed into a rigid cavity formed by the core assembly holes of the upper shell 1, and a full seal is achieved through welding of the core cover block. This provides the accelerometer core assembly with rigid support and axial positioning, enabling it to capture high-frequency vibration signals. The embedded encapsulation structure isolates the accelerometer core assembly from the transmission path of external force loads, and prevents deformation of the outer shell and the accelerometer core assembly, reducing cross-interference.

[0028] The upper housing 1 of this invention has a connector hole on one side, and a four-core connector 18 is connected to the connector hole. A wire hole 21 is opened inside the threaded column, and the core insulating block 16 has a central hole that matches the position of the wire hole 21 for the signal line to pass through. A lower wire hole 22 is opened on the lower housing 6. The lower wire hole 22 is connected to the connector hole through an internal channel formed after the housing is assembled or a reserved wiring path, so that one end of the acceleration signal wire is electrically connected to the electrode plate 15, and the other end passes through the hole and is electrically connected to the four-core connector 18.

[0029] It should be noted that the present invention plans the internal routing path of the sensor signal wire. Specifically, after the acceleration signal wire is soldered to the center of the electrode plate 15, it passes downward through the central hole of the core insulating block 16 and enters the micro wire hole inside the threaded post of the upper housing 1.

[0030] The wires travel downwards inside the housing, converging with the force signal line exiting the force core hole of the first force core insulating ring and the pressure signal line ascending from the bottom of the lower housing 6, within the pre-reserved routing space or channel inside the lower housing. All these wires are guided together to the connector hole on the side wall of the upper housing 1. Finally, the three signal lines and the ground line are soldered to the four independent pins inside the four-core connector 18, respectively, to achieve electrical connection.

[0031] Furthermore, the four-core connector can be sealed and fixed to the housing connector hole using laser welding. All wires are shielded and protected by the metal housing, avoiding external electromagnetic interference and improving the reliability of the sensor.

[0032] The force core assembly of the present invention includes: a first force core insulating ring 2, a second force core insulating ring 20, a cylindrical ceramic 3, a conical insulating block 4, and a force core conical support block 5. The first force core insulating ring 2 abuts against the bottom of the inner groove, and the second force core insulating ring 20 is installed on the outer wall of the threaded countersunk hole of the lower housing 6.

[0033] A conical insulating block 4 is fitted onto the outer wall of the threaded column, a conical support block 5 is fitted onto the outer wall of the conical insulating block 4, and a cylindrical ceramic 3 is fitted onto the outer wall of the conical support block 5. One end of the cylindrical ceramic 3 abuts against the first insulating ring 2, and the other end abuts against the second insulating ring 20. The first insulating ring has a core hole for signal routing.

[0034] It should be noted that the conical insulating block 4 is fitted onto the threaded post of the upper housing 1, and its outer surface is conical. The inner surface of the force core conical support block 5 is conical, and its outer surface is cylindrical, covering the conical insulating block 4.

[0035] When the upper housing 1 is subjected to a downward axial force, the conical insulating block 4 moves downward accordingly. Due to the action of the conical surface, the conical support block is forced to overcome the friction of the mating surface, generating radial expansion. The expansion force is applied to the inner wall of the cylindrical ceramic 3. Under the action of the radial clamping force, the cylindrical ceramic 3 undergoes shear deformation, thereby outputting an electric charge signal. The two core insulating rings not only provide insulation but also serve as rigid support end faces, ensuring that the deformation of the cylindrical ceramic 3 occurs in the expected sensitive area. The conical wedge structure has a force amplification effect, which can convert a small axial displacement into a large radial displacement and compressive force, thereby improving the sensor sensitivity. The bidirectional symmetrical expansion mode ensures that the force on the piezoelectric ceramic is absolutely uniform in the circumferential direction, eliminating nonlinear errors and pyroelectric interference caused by uneven force.

[0036] The pressure core assembly of the present invention includes: a pressure core insulating seat 7, a pressure core cylindrical ceramic 8, a conical support block 9, a pressure core conical diaphragm 10, and a pressure core insulating ring 11.

[0037] The pressure core insulating seat 7 is located at the bottom of the pressure-sensitive assembly hole; the pressure core conical diaphragm 10 is provided with a conical head and a flat circular section connected to the conical head; the flat circular section abuts against the end of the pressure-sensitive assembly hole, and the conical head extends to the position of the pressure core insulating seat 7 inside the hole. A conical support block 9 is sleeved on the outer wall of the conical head, and a pressure core cylindrical ceramic 8 is sleeved on the outer wall of the conical support block 9; the pressure core insulating ring 11 is installed at the connection position between the conical head and the flat circular section.

[0038] It should be noted that the flat section of the conical diaphragm 10 of the pressure core is sealed and welded to the lower housing 6, isolating the pressure medium from the outside. When external pressure acts on the outside of the flat section of the diaphragm, the conical part in the central area of ​​the diaphragm will flex upward. This upward displacement directly pushes against the upper conical support block 9.

[0039] When the conical support block 9 is pushed upwards, it expands outwards along its inner conical surface, thereby uniformly compressing the outer pressure core cylindrical ceramic 8. The pressure core insulating seat 7 and the pressure core insulating ring 11 provide an insulating mounting carrier for the pressure core cylindrical ceramic 8. The pressure core assembly is installed in a countersunk hole at the bottom of the lower housing, structurally connected in series with the force and acceleration sensors above, but isolated in mechanical transmission. The pressure signal is sensed through the diaphragm and does not couple with the upper housing boss that measures static force, avoiding crosstalk between the two signals. The conical diaphragm design ensures the flexibility required for pressure sensitivity, while the conical head structure provides the rigidity to push the conical support block, ensuring the sensitivity and stability of the pressure signal conversion, enabling the sensor to accurately measure both static load and dynamic pressure simultaneously.

[0040] The following are embodiments of the assembly method provided in this disclosure. This assembly method belongs to the same inventive concept as the composite sensor based on the compression-expansion structure in the above embodiments. For details not described in detail in the embodiments of the assembly method, please refer to the embodiments of the composite sensor based on the compression-expansion structure described above.

[0041] Assembly methods include: S1: The core insulating ring 13 is fitted and installed on the inner wall of the core assembly hole at the first end of the upper housing 1. The core insulating block 16 is placed at the bottom of the core assembly hole. Then, the electrode sheet 15, the core sheet ceramic 14, the core mass block 17 and the core cover block 12 are stacked sequentially on the upper end of the core insulating block 16. The acceleration signal core wire is passed through the wire hole opened inside the threaded column of the upper housing 1. After applying axial preload, the core cover block 12 is welded and sealed to the upper housing 1.

[0042] S2: The first force core insulating ring 2 is abutted against the bottom of the inner groove of the upper housing 1. The conical insulating block 4 is sleeved on the outer wall of the threaded post of the upper housing 1. The force core conical support block 5 is sleeved on the outer wall of the conical insulating block 4. The cylindrical ceramic 3 is sleeved on the outer wall of the force core conical support block 5. The second force core insulating ring 20 is sleeved on the end of the cylindrical ceramic 3 and abuts against the outer wall of the threaded countersunk hole at the first end of the lower housing 6. The force signal core wire is passed out from the connector hole at the side end of the upper housing 1. The threaded countersunk hole at the first end of the lower housing 6 is screwed into the threaded post of the upper housing 1. After tightening to the set torque, the upper housing 1 and the lower housing 6 are welded and fixed.

[0043] S3: Place the pressure core insulating seat 7 at the bottom of the pressure-sensitive assembly hole at the second end of the lower housing 6, place the conical support block 9 on the pressure core insulating seat 7, sleeve the pressure core cylindrical ceramic 8 on the outer wall of the conical support block 9, sleeve the pressure core insulating ring 11 on the connection position between the cone head and the flat section of the pressure core conical diaphragm 10, insert the cone head of the pressure core conical diaphragm 10 inward into the pressure-sensitive assembly hole, so that the cone head contacts the inner conical surface of the conical support block 9, so that the flat section of the pressure core conical diaphragm 10 abuts against the end step of the pressure-sensitive assembly hole, apply axial preload, weld the flat section to the lower housing 6 for sealing, and pass the pressure signal core wire through the lower lead wire hole opened on the lower housing 6.

[0044] S4: The acceleration signal core wire and pressure signal core wire passing through the lower lead wire hole, as well as the force signal core wire passing through the connector hole of the upper housing 1, are led from the internal channels of the lower housing 6 and the upper housing 1 to the connector hole, respectively. The acceleration signal core wire, force signal core wire and pressure signal core wire are then soldered to the four pins of the four-core connector 18.

[0045] S5: Insert the four-core connector 18 into the connector hole on the side of the upper housing 1, and seal and fix the outer shell of the four-core connector 18 to the upper housing 1 by laser welding to complete the assembly of the composite sensor.

[0046] The assembly method integrates three independent sensing units—acceleration, static force, and pressure—into a single sensor through coaxial stacking and sequential assembly. This ensures the alignment of the three measurement axes, eliminating installation deviations and phase delays that are unavoidable when using multiple independent sensors. During assembly, the signal wires of all sensing elements pass through pre-designed insulated channels inside the housing and are centrally soldered to a four-pin connector 18. This shielding of the charge signal throughout the transmission path by the metal housing reduces electromagnetic interference. Multiple welding points on the core cover, upper and lower housings, pressure core conical diaphragm, and connectors achieve a fully sealed sensor.

[0047] In some specific embodiments, the sensing methods of the composite sensor include the following seven sensing modes: 1. When an external static compressive force acts on the annular boss of the upper housing 1, and no external pressure acts on the flat section of the conical diaphragm 10 of the pressure core, and no axial vibration or impact acceleration acts on the sensor as a whole, the execution mode based on force sensing conditions includes the following steps: S101: The external static compressive force is transmitted through the upper shell 1 to the conical insulating block 4 sleeved on the outer wall of the threaded column, forcing the conical insulating block 4 to wedge downward along the axis between the two force core conical support blocks 5.

[0048] S102: After being wedged, the cone-shaped support block 5 of the force core expands radially outward, squeezing the cylindrical ceramic 3 sleeved on the outer wall. Due to the piezoelectric effect, the cylindrical ceramic 3 generates a charge signal that is proportional to the external static compressive force. The charge signal is output through the force signal core wire pre-welded to the metal layer on the outside of the cylindrical ceramic 3.

[0049] S103: The output force signal core wire is gathered through the connector hole on the side of the upper housing 1 to one of the pins of the four-core connector 18, while the pressure signal core wire and acceleration signal core wire have no signal input to the other pins of the four-core connector 18.

[0050] S104: The four-core connector 18 transmits the charge signal on the force signal core wire to the external signal acquisition device through the external cable to realize the monitoring of static compressive force signal.

[0051] Second: When external pressure acts on the flat section of the conical diaphragm 10 of the pressure core, and no external static pressure force acts on the annular boss at the first end of the upper housing 1, and no axial vibration or impact acceleration acts on the sensor as a whole, the execution mode based on pressure sensing conditions includes the following steps: S201: External pressure acts on the flat section of the conical diaphragm 10 of the pressure core, causing the flat section to move upward axially, which in turn pushes the cone head upward against the conical support block 9 fitted on the outer wall of the cone head. The conical support block 9 expands outward radially, squeezing the cylindrical ceramic pressure core 8 fitted on its outer wall. The cylindrical ceramic pressure core 8 generates a charge signal proportional to the external pressure due to the piezoelectric effect. The charge signal is output through the pressure signal core wire pre-welded to the outer metal layer of the cylindrical ceramic pressure core 8.

[0052] S202: The output pressure signal core wire is gathered through the lower wire hole of the lower housing 6 and the connector hole on the side of the upper housing 1 to one of the pins of the four-core connector 18.

[0053] S203: The four-core connector 18 transmits the charge signal on the pressure signal core wire to an external signal acquisition device through a connected external cable, thereby enabling pressure signal monitoring.

[0054] 3. When the sensor as a whole is subjected to axial vibration or impact acceleration, and there is no external static compressive force acting on the annular boss at the first end of the upper housing 1, and no external pressure acting on the flat section of the conical diaphragm 10 of the pressure core, the execution mode based on acceleration sensing conditions includes the following steps: S301: Axial vibration or impact acceleration causes the core mass block 17 to generate an axial inertial force. This inertial force compresses the core sheet ceramic 14 adjacent to the core mass block 17. The core sheet ceramic 14 generates a charge signal proportional to the acceleration value due to the piezoelectric effect. The charge signal is output through the electrode sheet 15 sandwiched between the core sheet ceramic 14 and the core insulating block 16.

[0055] S302: The output acceleration signal core wires converge to one of the pins of the four-core connector 18 via the wire hole inside the threaded post of the upper housing 1, the center hole of the core insulating block 16, and the connector hole at the side end of the upper housing 1. The force signal core wires and pressure signal core wires have no signal input to the other pins of the four-core connector 18.

[0056] S303: The four-core connector 18 transmits the charge signal on the acceleration signal core wire to an external signal acquisition device through the external cable, thereby enabling the monitoring of the acceleration signal.

[0057] 4. When there is an external static compressive force acting on the annular boss of the upper shell 1, and an external pressure acting on the flat section of the conical diaphragm 10 of the pressure core, and there is no axial vibration or impact acceleration, the execution method based on force sensing + pressure sensing conditions includes the following steps: The external static compressive force is transmitted through the upper shell 1 to the conical insulating block 4 sleeved on the outer wall of the threaded column, forcing the conical insulating block 4 to wedge downward along the axis between the two force core conical support blocks 5.

[0058] After being wedged, the cone-shaped support block 5 of the force core expands radially outward, squeezing the cylindrical ceramic 3 fitted on its outer wall. Due to the piezoelectric effect, the cylindrical ceramic 3 generates an electric charge signal that is proportional to the external static compressive force. The electric charge signal is output through the force signal core wire pre-welded to the metal layer on the outside of the cylindrical ceramic 3.

[0059] Simultaneously, external pressure acts on the flat section of the conical diaphragm 10 of the pressure core, causing the flat section to move upward axially, which in turn pushes the cone head upward against the conical support block 9 fitted on the outer wall of the cone head. The conical support block 9 expands radially outward, squeezing the cylindrical ceramic pressure core 8 fitted on its outer wall. The cylindrical ceramic pressure core 8 generates a charge signal proportional to the external pressure due to the piezoelectric effect. The charge signal is output through the pressure signal core wire pre-welded to the outer metal layer of the cylindrical ceramic pressure core 8.

[0060] The output force signal core wire is gathered through the connector hole at the side end of the upper housing 1 to the first pin of the four-core connector 18. The output pressure signal core wire is gathered through the lower wire hole of the lower housing 6 and the connector hole at the side end of the upper housing 1 to the second pin of the four-core connector 18. The acceleration signal core wire has no signal input to the third pin of the four-core connector 18.

[0061] The four-core connector 18 transmits the charge signals on the force signal core and pressure signal core to an external signal acquisition device simultaneously via an external cable, enabling simultaneous monitoring of static compressive force and external pressure.

[0062] 5. When there is an external static compressive force acting on the annular boss of the upper shell 1, and axial vibration or impact acceleration, but no external pressure acting on the flat section of the conical diaphragm 10 of the pressure core, the execution method based on force sensing + acceleration sensing conditions includes the following steps: The external static compressive force is transmitted through the upper shell 1 to the force core conical insulating block 4 sleeved on the outer wall of the threaded column, forcing the force core conical insulating block 4 to wedge downward along the axis between the two force core conical support blocks 5.

[0063] After being wedged, the cone-shaped support block 5 expands radially outward, squeezing the cylindrical ceramic core 3 fitted on its outer wall. The cylindrical ceramic core 3 generates a charge signal proportional to the external static compressive force due to the piezoelectric effect. The charge signal is output through the force signal core wire pre-welded to the outer metal layer of the cylindrical ceramic core 3.

[0064] Axial vibration or impact acceleration causes the core mass block 17 to generate an axial inertial force. The inertial force compresses the acceleration core sheet ceramic 14 adjacent to the core mass block 17. Due to the piezoelectric effect, the acceleration core sheet ceramic 14 generates a charge signal proportional to the acceleration value. The charge signal is output through the electrode sheet sandwiched between the acceleration core sheet ceramic 14 and the acceleration core insulating block 16.

[0065] The output force signal core wire is gathered through the connector hole at the side end of the upper housing 1 to the first pin of the four-core connector 18. The output acceleration signal core wire is gathered through the wire hole inside the threaded post of the upper housing 1, the center hole of the acceleration core insulating block 16, and the connector hole at the side end of the upper housing 1 to the second pin of the four-core connector 18. The pressure signal core wire has no signal input to the third pin of the four-core connector 18.

[0066] The four-core connector 18 transmits the charge signals on the force signal core and acceleration signal core to an external signal acquisition device simultaneously via an external cable, enabling simultaneous monitoring of static compressive force and vibration acceleration.

[0067] Six: When there is simultaneous external pressure acting on the flat section of the conical diaphragm 10 of the pressure core, and axial vibration or impact acceleration, but no external static compressive force acting on the annular boss of the upper housing 1, the execution mode based on pressure sensing + acceleration sensing conditions includes the following steps: External pressure acts on the flat section of the conical diaphragm 10 of the pressure core, causing the flat section to move upward axially, which in turn pushes the cone head upward against the conical support block 9 fitted on the outer wall of the cone head. The conical support block 9 expands radially outward, squeezing the cylindrical ceramic pressure core 8 fitted on its outer wall. The cylindrical ceramic pressure core 8 generates a charge signal proportional to the external pressure due to the piezoelectric effect. This charge signal is output through the pressure signal core wire pre-welded to the outer metal layer of the cylindrical ceramic pressure core 8.

[0068] Axial vibration or impact acceleration causes the core mass block 17 to generate an axial inertial force. This inertial force compresses the core sheet ceramic 14 adjacent to the core mass block 17. The core sheet ceramic 14 generates a charge signal proportional to the acceleration value due to the piezoelectric effect. This charge signal is output through the electrode sheet 15 sandwiched between the core sheet ceramic 14 and the core insulating block 16.

[0069] The output pressure signal core wires converge to the first pin of the four-core connector 18 via the lower wire hole of the lower housing 6 and the connector hole at the side end of the upper housing 1. The output acceleration signal core wires converge to the second pin of the four-core connector 18 via the wire hole inside the threaded post of the upper housing 1, the center hole of the core insulating block 16, and the connector hole at the side end of the upper housing 1.

[0070] The four-core connector 18 transmits the charge signals on the pressure signal core and acceleration signal core to an external signal acquisition device simultaneously via an external cable, enabling simultaneous monitoring of external pressure and vibration acceleration.

[0071] 7. When there is a simultaneous external static compressive force acting on the annular boss at the first end of the upper housing 1, external pressure acting on the flat section of the conical diaphragm 10 of the pressure core, and axial vibration or impact acceleration, the execution mode based on the conditions of force sensing + pressure sensing + acceleration sensing includes the following steps: The external static compressive force is transmitted through the upper housing 1 to the conical insulating block 4 sleeved on the outer wall of the threaded column, forcing the conical insulating block 4 to wedge downward along the axial direction between the conical support block 5 of the force core.

[0072] After being wedged, the cone-shaped support block 5 of the force core expands radially outward, squeezing the cylindrical ceramic 3 fitted on its outer wall. The cylindrical ceramic 3 generates an electric charge signal proportional to the external static compressive force due to the piezoelectric effect. This electric charge signal is output through the force signal core wire pre-welded to the metal layer on the outside of the cylindrical ceramic 3.

[0073] External pressure acts on the flat section of the conical diaphragm 10 of the pressure core, causing the flat section to move upward axially, which in turn pushes the cone head upward against the conical support block 9 fitted on the outer wall of the cone head. The conical support block 9 expands radially outward, squeezing the cylindrical ceramic pressure core 8 fitted on its outer wall. The cylindrical ceramic pressure core 8 generates a charge signal proportional to the external pressure due to the piezoelectric effect. This charge signal is output through the pressure signal core wire pre-welded to the outer metal layer of the cylindrical ceramic pressure core 8.

[0074] Axial vibration or impact acceleration causes the core mass block 17 to generate an axial inertial force. The inertial force compresses the core sheet ceramic 14 adjacent to the core mass block 17. The core sheet ceramic 14 generates a charge signal proportional to the acceleration value due to the piezoelectric effect. This charge signal is output through the electrode plate 15 sandwiched between the core sheet ceramic 14 and the core insulating block 16.

[0075] The output force signal core wire is gathered to the first pin of the four-core connector 18 through the connector hole at the side end of the upper housing 1. The output pressure signal core wire is gathered to the second pin of the four-core connector 18 through the lower wire hole of the lower housing 6 and the connector hole at the side end of the upper housing 1. The output acceleration signal core wire is gathered to the third pin of the four-core connector 18 through the wire hole inside the threaded post of the upper housing 1, the center hole of the core insulating block 16, and the connector hole at the side end of the upper housing 1.

[0076] The four-core connector 18 transmits the charge signals on the force signal core, pressure signal core, and acceleration signal core to an external signal acquisition device simultaneously via an external cable, enabling simultaneous monitoring of three physical quantities: static compressive force, external pressure, and vibration acceleration.

[0077] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0078] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A composite sensor based on a compression-expansion structure, characterized in that, include: Core assembly, upper housing, and lower housing; One end of the upper housing has a core assembly hole, and an acceleration core assembly for sensing impact acceleration is installed inside the core assembly hole. The upper housing is provided with an inner groove, and a threaded post is provided in the middle of the inner groove; the first end of the lower housing is provided with a threaded countersunk hole that matches the threaded post; the lower housing and the upper housing are detachably connected by threads. The force core assembly is mounted on the threaded post of the upper housing and abuts against the threaded counterbore wall of the lower housing. The force core assembly is used to convert the externally applied static compressive force into lateral extrusion force through compression and expansion, so that the piezoelectric ceramic generates an electric charge signal to realize force signal monitoring. The lower housing has a pressure-sensitive assembly hole at the second end. Inside the pressure-sensitive assembly hole is a pressure core assembly that uses a conical diaphragm to withstand external pressure, drives a conical support block to expand laterally, and causes the piezoelectric ceramic to generate an electric charge signal, thereby realizing pressure signal monitoring. An annular boss is provided at the outer end of the core assembly hole of the upper shell; The acceleration core assembly includes: a core cover block, a core insulating ring, a core sheet ceramic, electrode sheets, a core insulating block, and a core mass block; The core insulating ring is fitted onto the core assembly hole wall to achieve circumferential insulation of the core assembly hole wall; The core insulating block is located at the bottom of the core assembly hole, and the upper end of the core insulating block is sequentially provided with an electrode plate, a core sheet ceramic, a core mass block, and a core cover block. A connector hole is provided on one side of the upper housing, and a four-pin connector is connected to the connector hole; The core assembly includes: a first core insulating ring, a second core insulating ring, a cylindrical ceramic, a conical insulating block, and a core conical support block; The first core insulating ring abuts against the bottom of the inner groove, and the second core insulating ring is installed on the outer wall of the threaded countersunk hole of the lower housing; A conical insulating block is fitted onto the outer wall of the threaded column, a conical support block for the core is fitted onto the outer wall of the conical insulating block, and a cylindrical ceramic is fitted onto the outer wall of the conical support block for the core. One end of the cylindrical ceramic abuts against the first core insulating ring, and the other end abuts against the second core insulating ring; The core insulating ring is provided with core holes for signal routing; The pressure core assembly includes: a pressure core insulating base, a pressure core cylindrical ceramic, a conical support block, a pressure core conical diaphragm, and a pressure core insulating ring; The pressure core insulating seat is located at the bottom of the pressure-sensitive assembly hole; The pressure core conical diaphragm is provided with a cone head and a flat circular section connected to the cone head; the flat circular section abuts against the end of the pressure-sensitive assembly hole, and the cone head extends to the position of the pressure core insulating seat inside the hole; A conical support block is fitted on the outer wall of the cone head, and a pressure core cylindrical ceramic is fitted on the outer wall of the conical support block; The pressure core insulating ring is installed at the connection point between the cone head and the flat section.

2. The composite sensor based on a compression-expansion structure according to claim 1, characterized in that, The threaded column has a wire hole inside, and the core insulating block has a central hole that matches the position of the wire hole for the signal line to pass through. The lower housing has a lower wire hole, which is connected to the connector hole through an internal channel formed after the housing is assembled or a reserved wiring path, so that one end of the acceleration signal wire is electrically connected to the electrode plate, and the other end passes through the hole and is electrically connected to the four-core connector.

3. An assembly method, characterized in that, The method is used to assemble a composite sensor based on a compression-expansion structure as described in any one of claims 1 to 2; Assembly methods include: The accelerometer core insulating ring is attached to the inner wall of the core assembly hole at the first end of the upper housing. The accelerometer core insulating block, electrode sheet, accelerometer core sheet ceramic, core mass block and accelerometer core cover block are stacked in sequence at the bottom of the hole. The accelerometer signal core wire is passed out from the wire hole of the threaded column of the upper housing. After applying pre-tightening force, the sealing cover block is welded. The first force core insulating ring is placed against the bottom of the groove inside the upper housing. The force core conical insulating block is fitted onto the outer wall of the threaded column. The force core conical support block is fitted onto the outer wall of the conical insulating block. The force core cylindrical ceramic is fitted onto the outer wall of the support block. The second force core insulating ring is fitted onto the end of the ceramic and abuts against the outer wall of the threaded countersunk hole of the lower housing. The force signal core wire is passed out from the connector hole of the upper housing. The lower housing and the upper housing are screwed together to the set torque and then welded and fixed. Place the pressure core insulating seat at the bottom of the pressure-sensitive assembly hole at the second end of the lower housing, place the conical support block on the insulating seat, and fit the pressure core cylindrical ceramic. Fit the pressure core insulating ring onto the connection between the cone head and the flat section of the conical diaphragm of the pressure core. Insert the cone head inward into the pressure-sensitive assembly hole so that the cone head contacts the inner conical surface of the conical support block and the flat section abuts against the end step of the hole. After applying pre-tightening force, weld the sealing flat section to the lower housing, and pass the pressure signal core wire out from the lower lead wire hole of the lower housing. The three signal core wires are led through the internal channel of the housing to the connector hole and soldered to the four pins of the four-core connector respectively; The four-pin connector is inserted into the connector hole on the upper housing and sealed and fixed by laser welding.

4. A sensing method, characterized in that, The method is implemented based on the composite sensor based on the compression-expansion structure as described in any one of claims 1 to 2; When the annular boss of the upper shell is subjected to static compressive force, the compressive force is transmitted through the upper shell to the conical insulating block, which wedges downward into the conical support block of the force core. The conical support block of the force core expands radially to compress the cylindrical ceramic to generate force signal charge, which is output to the four-core connector through the force signal core wire. When the conical diaphragm of the pressure core at the bottom of the housing is subjected to external pressure, the flat section moves upward, causing the cone head to push the conical support block. The conical support block expands radially, squeezing the cylindrical ceramic of the pressure core to generate a pressure signal charge, which is output to the four-core connector via the pressure signal core wire. When the sensor as a whole is subjected to axial vibration or impact acceleration, the core mass block generates inertial force to compress the acceleration core sheet ceramic to generate acceleration signal charge, which is output to the four-pin connector through the electrode sheet; The four-pin connector transmits at least one received charge signal to the signal acquisition device via an external cable.

5. The sensing method according to claim 4, characterized in that, In the method, when the annular boss of the upper shell is subjected to static compressive force, the compressive force is successively wedged into the conical insulating block and radially expanded by the conical support block of the force core, squeezing the cylindrical ceramic of the force core to generate force signal charge, which is then sent to the four-core connector via the force signal core wire. When the conical diaphragm of the pressure core at the bottom of the housing is subjected to external pressure, the pressure is axially displaced through the flat section, pushed by the cone head, and radially expanded by the conical support block, squeezing the cylindrical ceramic of the pressure core to generate a pressure signal charge, which is then sent to the four-core connector through the pressure signal core wire. When the sensor as a whole is subjected to axial vibration or impact acceleration, the inertial force of the core mass block compresses the acceleration core sheet ceramic to generate acceleration signal charge, which is then sent to the four-core connector through the electrode sheet. The four-pin connector synchronously transmits any one or more received charge signals to the signal acquisition device via an external cable.

6. The sensing method according to claim 4, characterized in that, In this method, when external pressure is applied to the flat section of the conical diaphragm of the pressure core and the sensor as a whole is subjected to axial vibration or impact acceleration, the conical diaphragm of the pressure core moves upward and expands radially through the conical support block to compress the cylindrical ceramic of the pressure core, generating a pressure signal charge. At the same time, the inertial force of the core mass block compresses the sheet-like ceramic of the acceleration core, generating an acceleration signal charge. The pressure signal charge is sent to different pins of the four-pin connector via the pressure signal core wire and the acceleration signal charge via the electrode plates. The four-pin connector transmits the two charge signals synchronously to the signal acquisition device through an external cable. In this method, when the annular boss of the upper shell is subjected to static compressive force, external pressure acts on the flat section of the conical diaphragm of the pressure core, and the sensor as a whole is subjected to axial vibration or impact acceleration, the static compressive force is wedged in by the conical insulating block, and the radial expansion of the conical support block of the pressure core compresses the cylindrical ceramic of the pressure core to generate force signal charge; the external pressure is displaced upward by the conical diaphragm of the pressure core, and the radial expansion of the conical support block compresses the cylindrical ceramic of the pressure core to generate pressure signal charge; the axial vibration or impact acceleration causes the inertial force of the core mass block to compress the plate-shaped ceramic of the acceleration core to generate acceleration signal charge; the force signal charge, pressure signal charge, and acceleration signal charge are respectively sent to the three different pins of the four-core connector through their respective signal core wires, and the four-core connector transmits the three charge signals synchronously to the signal acquisition device through an external cable.

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